Processes for designing cross-linkable polycarbonates and articles formed therefrom

ABSTRACT

Articles having improved flame retardance and chemical resistance properties can be made from blends containing a cross-linkable polycarbonate resin having repeating units derived from a dihydroxybenzophenone. Predictive equations can be used to relate properties of the blend and the polycarbonate resin to the fmal properties of the article, and permit design of articles with desired combinations of properties.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/015,250, filed on Jun. 20, 2014, the entirety of which ishereby fully incorporated by reference.

BACKGROUND

The present disclosure relates to processes for preparing cross-linkablepolycarbonates and articles formed therefrom that have certain desiredproperties or combinations of properties.

Polycarbonates (PC) are thermoplastic resins with desirable propertiessuch as high impact strength and toughness, transparency, and heatresistance. However, they also drip when exposed to a flame, and thisbehavior worsens as wall thickness decreases. This is undesirable forapplications requiring V0 or 5VA performance. It would be desirable tobe able to create polymeric compositions whose properties can bepredicted, permitting the design of and balance between desiredcombinations of properties.

BRIEF DESCRIPTION

The present disclosure relates to processes for preparing articleshaving desired properties and combinations of properties. The articlesare formed from a polymeric composition that includes a cross-linkablepolycarbonate resin having a photoactive group derived from adihydroxybenzophenone. Upon exposure to UV radiation, crosslinkingoccurs and a combination of properties is desirably obtained.

The articles are prepared from polymeric compositions that includecross-linkable polycarbonate resins containing a photoactive groupderived from a dihydroxybenzophenone. Upon exposure to ultravioletradiation, the cross-linkable polycarbonate resin will crosslink withitself and/or with other polymeric base resins, improving overallchemical resistance, flame retardance, and other characteristics of thearticles. Based on certain formulations and equations disclosed herein,the polycarbonate resins and the polymeric compositions can bespecifically created to achieve certain properties when exposed to aselected dosage of UV radiation.

Briefly, several predictive equations are identified herein forselecting and predicting a property of an article based on properties ofthe cross-linkable polycarbonate and the polymeric composition/blendused to make the article. Equation 1 predicts the average V0. Equation 2predicts the percentage retention of tensile elongation after UVexposure. Equation 3 predicts the Delta YI after UV exposure. Equation 4predicts the Delta % T after UV exposure. Equation 5 predicts the gelthickness after UV exposure.

Disclosed in various embodiments are processes for preparing an articlethat has a high probability of passing a UL94 V0 test, comprising:providing a polymeric composition to be exposed to a dosage (D) of UVAradiation, wherein the polymeric composition comprises: a cross-linkablepolycarbonate resin including repeating units derived from adihydroxybenzophenone; and optionally one or more polymeric base resins;wherein the cross-linkable polycarbonate resin contains a molarpercentage of the dihydroxybenzophenone (MOL %); and wherein thepolymeric composition has: a molecular weight increase of polymericcomponents therein after exposure to UV radiation (MW_I), a melt flowrate (MF), and a weight percentage of the cross-linkable polycarbonateresin (WP); forming an article from the polymeric composition; andexposing the formed article to the dosage; wherein D, MOL %, MW_I, MF,and WP are determined based on the flame performance Equation 1described herein for obtaining V0_Avg.

Disclosed in various embodiments are processes for preparing an articlethat has a high probability of passing a UL94 V0 test, comprising:designing a polymeric composition to be exposed to a selected dosage (D)of UVA radiation, wherein the polymeric composition comprises: across-linkable polycarbonate resin including repeating units derivedfrom a dihydroxybenzophenone; and optionally one or more polymeric baseresins; wherein the cross-linkable polycarbonate resin contains aselectable molar percentage of the dihydroxybenzophenone (MOL %), andthe polymeric composition has a selectable molecular weight increaseafter exposure to UV radiation (MW_I), a selectable melt flow rate (MF),and a selectable weight percentage of the cross-linkable polycarbonateresin (WP); preparing the cross-linkable polycarbonate resin; optionallyblending the cross-linkable polycarbonate resin with the one or morepolymeric base resins to form the polymeric composition; forming anarticle from the polymeric composition; and exposing the formed articleto the selected dosage of UVA radiation; wherein D, MOL %, MW_I, MF, andWP are determined based on the flame performance Equation 1 describedherein for obtaining V0_Avg. The article has an average V0 (V0_Avg) thatis the average of (i) the probability of a first time pass in a UL94 V0test at a thickness of 1.2 millimeters (mm) after UV exposure andmeasured after 2 days of aging at room temperature, and (ii) theprobability of a first time pass in a UL94 V0 test at a thickness of 1.2mm after UV exposure and measured after 7 days of aging at 70° C. V0_Avgis at least 0.7.

In some embodiments, D, MOL %, MW_I, WP, and MF can also be determinedbased on the percentage retention of tensile elongation Equation 2described herein. The percentage retention of tensile elongation, % RE,should be at least 85%.

In addition, D, MOL %, and MW_I can also be determined based on theDelta YI Equation 3 described herein. The Delta YI should be at most 6.

In yet more variations, D, MOL %, MW_I, and MF can also be determinedbased on the Delta % T equation described herein. The Delta % T is 3.5or less.

Additionally, D, MOL %, MW_I, MF, and WP may also be determined based onthe gel thickness Equation 5 described herein. In embodiments, the gelthickness is at least 5 micrometers.

In particular embodiments, the polymeric composition comprises apolymeric base resin that is a bisphenol-A homopolycarbonate having aweight-average molecular weight of about 31,000, or is selected from theother polymeric base resins disclosed herein.

In some embodiments, MOL % is from 2.5 to 20. In other embodiments, MW_Iis from about 600 to about 11,000. In still other embodiments, MF isfrom about 5 to about 20. In various embodiments, WP is from 50 to 100.

The cross-linkable polycarbonate resin can be a copolymer or aterpolymer. Also disclosed herein are the cross-linkable polycarbonateresins prepared using these processes; the polymeric compositionsprepared in these processes; and articles formed by these processes. Thearticles can be, for example, a molded article, a film, a sheet, a layerof a multilayer film, or a layer of a multilayer sheet.

Additionally disclosed herein are processes for preparing an articlethat has a desired percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm, comprising: providing apolymeric composition to be exposed to a dosage (D) of UVA radiation,wherein the polymeric composition comprises: a cross-linkablepolycarbonate resin including repeating units derived from adihydroxybenzophenone; and optionally one or more polymeric base resins;wherein the cross-linkable polycarbonate resin contains a selectablemolar percentage of the dihydroxybenzophenone (MOL %); and wherein thepolymeric composition has: a molecular weight increase of polymericcomponents therein after exposure to UV radiation (MW_I), a melt flowrate (MF), and a weight percentage of the cross-linkable polycarbonateresin (WP); forming an article from the polymeric composition; andexposing the formed article to the dosage; wherein D, MOL %, MW_I, MF,and WP are determined based on the percentage retention of tensileelongation Equation 2 discussed herein.

Also disclosed in various embodiments herein are processes for preparingan article that has a desired percentage retention of tensile elongationafter exposure to acetone at a thickness of 3.2 mm. The processescomprise: designing a polymeric composition to be exposed to a selecteddosage (D) of UVA radiation, wherein the polymeric composition includes:a cross-linkable polycarbonate resin having repeating units derived froma dihydroxybenzophenone; and optionally one or more polymeric baseresins; wherein the cross-linkable polycarbonate resin contains aselectable molar percentage of the dihydroxybenzophenone (MOL %), andthe polymeric composition has a selectable molecular weight increaseafter exposure to UV radiation (MW_I), a selectable melt flow rate (MF),and a selectable weight percentage of the cross-linkable polycarbonateresin (WP); preparing the cross-linkable polycarbonate resin; optionallyblending the cross-linkable polycarbonate resin with the one or morepolymeric base resins to form the polymeric composition; forming anarticle from the polymeric composition; and exposing the formed articleto the selected dosage; wherein D, MOL %, MW_I, MF, and WP aredetermined based on the percentage retention of tensile elongationEquation 2 discussed herein. The percentage retention of tensileelongation is measured after exposure to acetone at a thickness of 3.2mm, and is at least 85.

In additional embodiments, D, MOL %, MW_I, WP, and MF can also bedetermined based on the flame performance Equation 1 discussed herein.Equation 1 provides an average V0 (V0_Avg), which is at least 0.7.

In addition, D, MOL %, and MW_I can also be determined based on theDelta YI Equation 3 described herein. The Delta YI should be at most 6.

In yet more variations, D, MOL %, MW_I, and MF can also be determinedbased on the Delta % T equation described herein. The Delta % T is 3.5or less.

Moreover, D, MOL %, MW_I, MF, and WP may also be determined based on thegel thickness Equation 5 described herein. In embodiments, the gelthickness is at least 5 micrometers.

In particular embodiments, the polymeric composition comprises apolymeric base resin that is a bisphenol-A homopolycarbonate having aweight-average molecular weight of about 31,000, or is selected from theother polymeric base resins disclosed herein.

In some embodiments, MOL % is from 2.5 to 20. In other embodiments, MW_Iis from about 600 to about 11,000. In still other embodiments, MF isfrom about 5 to about 20. In various embodiments, WP is from 50 to 100.

The cross-linkable polycarbonate resin can be a copolymer or aterpolymer. Also disclosed herein are the cross-linkable polycarbonateresins prepared using these processes; the polymeric compositionsprepared in these processes; and articles formed by these processes. Thearticles can be, for example, a molded article, a film, a sheet, a layerof a multilayer film, or a layer of a multilayer sheet.

Additionally disclosed in different embodiments herein are processes forpreparing an article that has a desired percentage retention of tensileelongation after exposure to acetone at a thickness of 3.2 mm,comprising: providing a polymeric composition to be exposed to a dosage(D) of UVA radiation, wherein the polymeric composition comprises: across-linkable polycarbonate resin including repeating units derivedfrom a dihydroxybenzophenone; and optionally one or more polymeric baseresins; wherein the cross-linkable polycarbonate resin contains aselectable molar percentage of the dihydroxybenzophenone (MOL %); andwherein the polymeric composition has: a molecular weight increase ofpolymeric components therein after exposure to UV radiation (MW_I), amelt flow rate (MF), and a weight percentage of the cross-linkablepolycarbonate resin (WP); forming an article from the polymericcomposition; and exposing the formed article to the dosage; wherein D,MOL %, and MW_I are determined based on the Delta YI Equation 3discussed herein.

Various additional embodiments are also related to processes forpreparing an article that has a low Delta YI after exposure to UVAradiation. The processes comprise: designing a polymeric composition tobe exposed to a selected dosage (D) of UVA radiation, wherein thepolymeric composition includes: a cross-linkable polycarbonate resinhaving repeating units derived from a dihydroxybenzophenone; andoptionally one or more polymeric base resins; wherein the cross-linkablepolycarbonate resin contains a selectable molar percentage of thedihydroxybenzophenone (MOL %), and the polymeric composition has aselectable molecular weight increase after exposure to UV radiation(MW_I), a selectable melt flow rate (MF), and a selectable weightpercentage of the cross-linkable polycarbonate resin (WP); preparing thecross-linkable polycarbonate resin; optionally blending thecross-linkable polycarbonate resin with the one or more polymeric baseresins to form the polymeric composition; forming an article from thepolymeric composition; and exposing the formed article to the selecteddosage; wherein D, MOL %, and MW_I are determined based on the Delta YIEquation 3 discussed herein. The Delta YI is at most 6.

In additional embodiments, D, MOL %, MW_I, WP, and MF can also bedetermined based on the flame performance Equation 1 discussed herein.Equation 1 provides an average V0 (V0_Avg), which is at least 0.7.

In some embodiments, D, MOL %, MW_I, WP, and MF can also be determinedbased on the percentage retention of tensile elongation Equation 2described herein. The percentage retention of tensile elongation, % RE,should be at least 85%.

In yet more variations, D, MOL %, MW_I, and MF can also be determinedbased on the Delta % T equation described herein. The Delta % T is 3.5or less.

Furthermore, D, MOL %, MW_I, MF, and WP may also be determined based onthe gel thickness Equation 5 described herein. In embodiments, the gelthickness is at least 5 micrometers.

In more particular embodiments, the polymeric composition comprises apolymeric base resin that is a polycarbonate. In some specificembodiments, the polymeric base resin is a bisphenol-A homopolycarbonatehaving a weight-average molecular weight of about 31,000, or is selectedfrom the other polymeric base resins disclosed herein.

In some embodiments, MOL % is from 2.5 to 20. In other embodiments, MW_Iis from about 600 to about 11,000. In still other embodiments, MF isfrom about 5 to about 20. In various embodiments, WP is from 50 to 100.

The cross-linkable polycarbonate resin can be a copolymer or aterpolymer. Also disclosed herein are the cross-linkable polycarbonateresins prepared using these processes; the polymeric compositionsprepared in these processes; and articles formed by these processes. Thearticles can be, for example, a molded article, a film, a sheet, a layerof a multilayer film, or a layer of a multilayer sheet.

Also disclosed in embodiments are articles formed from a polymericcomposition that comprises a cross-linkable polycarbonate resinincluding repeating units derived from a dihydroxybenzophenone, whereinthe article has at least two of the following three properties: (i) apFTP(V0) of at least 0.9 at a thickness of 1.2 mm after UV exposure andmeasured after 2 days of aging at room temperature; (ii) a percentageretention of tensile elongation of at least 85% after exposure toacetone at a thickness of 3.2 mm; and (iii) a Delta YI of less than 10,measured before UVA exposure and at least 48 hours after UVA exposure.The article may have all three of these properties.

These and other non-limiting characteristics are more particularlydescribed below.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are presented to illustrate the exemplaryembodiments disclosed herein and not to limit them.

FIG. 1 illustrates the formation of a cross-linkable polycarbonate resinfrom a dihydroxybenzophenone (4,4′-dihydroxybenzophenone), a carbonateprecursor (phosgene), a dihydroxy chain extender (bisphenol-A), and anend-capping agent (p-cumylphenol).

FIG. 2 illustrates the formation of a branched cross-linkablepolycarbonate resin from a dihydroxybenzophenone(4,4′-dihydroxybenzophenone), a carbonate precursor (phosgene), adihydroxy chain extender (bisphenol-A), an end-capping agent(p-cumylphenol), and a branching agent (1,1,1-tris-hydroxyphenylethane(THPE)).

FIG. 3 illustrates the crosslinking mechanism of the cross-linkablepolycarbonate.

FIG. 4 is a graph showing the predicted average V0 when applying themodel equation and holding the MFR, weight percentage of crosslinkableresin, and molecular weight increase constant.

FIG. 5 is a graph showing the predicted delta YI when applying the modelequation and holding the MFR, weight percentage of crosslinkable resin,and molecular weight increase constant.

FIG. 6 is a graph showing the predicted percentage retention of tensileelongation when applying the model equation and holding the MFR, weightpercentage of crosslinkable resin, and dosage (low value) constant.

FIG. 7 is a graph showing the predicted percentage retention of tensileelongation when applying the model equation and holding the MFR, weightpercentage of crosslinkable resin, and dosage (high value) constant.

FIG. 8 is a graph that illustrates the combination of three modelequations to identify a design space. The simulated article is formedfrom 100% of a crosslinkable polycarbonate containing 20 mole % ofrepeating units derived from 4,4′-dihydroxybenzophenone.

FIG. 9 is a graph that illustrates the combination of three modelequations to identify a design space. The simulated article is formedfrom 100% of a crosslinkable polycarbonate containing 10 mole % ofrepeating units derived from 4,4′-dihydroxybenzophenone.

FIG. 10 is a graph that illustrates the combination of three modelequations to identify a design space. The simulated article is formedfrom 100% of a crosslinkable polycarbonate containing 5 mole % ofrepeating units derived from 4,4′-dihydroxybenzophenone.

FIG. 11 is a graph that illustrates the combination of three modelequations to identify a design space. The simulated article is formedfrom a blend containing 50 wt % of a crosslinkable polycarbonatecontaining 5 mole % of repeating units derived from4,4′-dihydroxybenzophenone, and 50 wt % of a bisphenol-Ahomopolycarbonate having a weight-average molecular weight of about31,000. The permissible design spaces between FIG. 10 and FIG. 11 aredifferent.

DETAILED DESCRIPTION

In the following specification, the examples, and the claims whichfollow, reference will be made to some terms which are defined asfollows.

DEFINITIONS

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art. In case of conflict, the present document, includingdefinitions, will control. Preferred methods and materials are describedbelow, although methods and materials similar or equivalent to thosedescribed herein can be used in practice or testing of the presentinvention. All publications, patent applications, patents and otherreferences mentioned herein are incorporated by reference in theirentirety. The materials, methods, and examples disclosed herein areillustrative only and not intended to be limiting.

The singular forms “a,” “an,” and “the” include plural referents unlessthe context clearly dictates otherwise.

As used in the specification and in the claims, the open-endedtransitional phrases “comprise(s),” “include(s),” “having,”“contain(s),” and variants thereof require the presence of the namedingredients/steps and permit the presence of other ingredients/steps.These phrases should also be construed as disclosing the closed-endedphrases “consist of” or “consist essentially of” that permit only thenamed ingredients/steps and unavoidable impurities, and exclude otheringredients/steps.

Numerical values used herein should be understood to include numericalvalues which are the same when reduced to the same number of significantfigures and numerical values which differ from the stated value by lessthan the experimental error of the measurement technique described fordetermining the value.

All ranges disclosed herein are inclusive of the recited endpoint andindependently combinable (for example, the range of “from 2 grams to 10grams” is inclusive of the endpoints, 2 grams and 10 grams, and all theintermediate values).

The term “about” can be used to include any numerical value that cancarry without changing the basic function of that value. When used witha range, “about” also discloses the range defined by the absolute valuesof the two endpoints, e.g., “about 2 to about 4” also discloses therange “from 2 to 4.” The term “about” may refer to plus or minus 10% ofthe indicated number.

Compounds are described using standard nomenclature. Any position notsubstituted by an indicated group is understood to have its valencyfilled by a bond or a hydrogen atom. A dash (“-”) that is not betweentwo letters indicates a point of attachment for a substituent, e.g. —CHOattaches through the carbon atom.

The term “aliphatic” refers to an array of atoms that is not aromatic.The backbone of an aliphatic group is composed exclusively of carbon. Analiphatic group is substituted or unsubstituted. Exemplary aliphaticgroups are ethyl and isopropyl.

An “aromatic” radical has a ring system containing a delocalizedconjugated pi system with a number of pi-electrons that obeys HUckel'sRule. The ring system may include heteroatoms (e.g. N, S, Se, Si, 0), ormay be composed exclusively of carbon and hydrogen. Aromatic groups arenot substituted. Exemplary aromatic groups include phenyl, thienyl,naphthyl, and biphenyl.

An “ester” radical has the formula —CO—O—, with the carbon atom and theoxygen atom both bonded to carbon atoms. A “carbonate” radical has theformula —O—CO—O—, with the oxygen atoms both bonded to carbon atoms.Note that a carbonate group is not an ester group, and an ester group isnot a carbonate group.

A “hydroxyl” radical has the formula —OH, with the oxygen atom bonded toa carbon atom. A “carboxy” or “carboxyl” radical has the formula —COOH,with the carbon atom bonded to another carbon atom. A carboxyl group canbe considered as having a hydroxyl group. However, please note that acarboxyl group participates in certain reactions differently from ahydroxyl group. An “anhydride” radical has the formula —CO—O—CO—, withthe carbonyl carbon atoms bonded to other carbon atoms. This radical canbe considered equivalent to two carboxyl groups. The term “acid halide”refers to a radical of the formula —CO—X, with the carbon atom bonded toanother carbon atom.

The term “alkyl” refers to a radical composed entirely of carbon atomsand hydrogen atoms which is fully saturated. The alkyl radical may belinear, branched, or cyclic.

The term “alkyl” refers to a fully saturated radical composed entirelyof carbon atoms and hydrogen atoms. The alkyl radical may be linear,branched, or cyclic. The term “aryl” refers to an aromatic radicalcomposed exclusively of carbon and hydrogen. Exemplary aryl groupsinclude phenyl, naphthyl, and biphenyl. The term “hydrocarbon” refers toa radical which is composed exclusively of carbon and hydrogen. Bothalkyl and aryl groups are considered hydrocarbon groups. The term“heteroaryl” refers to an aromatic radical containing at least oneheteroatom. Note that “heteroaryl” is a subset of aromatic, and isexclusive of “aryl”.

The term “halogen” refers to fluorine, chlorine, bromine, and iodine.The term “halo” means that the substituent to which the prefix isattached is substituted with one or more independently selected halogenradicals.

The term “alkoxy” refers to an alkyl radical which is attached to anoxygen atom, i.e. —O—C_(n)H_(2n+1). The term “aryloxy” refers to an arylradical which is attached to an oxygen atom, e.g. —O—C₆H₅.

An “alkenyl” radical is composed entirely of carbon atoms and hydrogenatoms and contains a carbon-carbon double bond that is not part of anaromatic structure. An exemplary alkenyl radical is vinyl (—CH═CH₂).

The term “alkenyloxy” refers to an alkenyl radical which is attached toan oxygen atom, e.g. —O—CH═CH₂. The term “arylalkyl” refers to an arylradical which is attached to an alkyl radical, e.g. benzyl (—CH₂—C₆H₅).The term “alkylaryl” refers to an alkyl radical which is attached to anaryl radical, e.g. tolyl (—C₆H₄—CH₃).

The term “substituted” refers to at least one hydrogen atom on the namedradical being substituted with another functional group, such ashalogen, —CN, or —NO₂. However, the functional group is not hydroxyl,carboxyl, ester, acid halide, or anhydride. Besides the aforementionedfunctional groups, an aryl group may also be substituted with alkyl oralkoxy. An exemplary substituted aryl group is methylphenyl.

The term “copolymer” refers to a molecule derived from two or morestructural unit or monomeric species, as opposed to a homopolymer, whichis a molecule derived from only one structural unit or monomer. The term“terpolymer” refers to a molecule derived specifically from only threedifferent monomers.

The terms “Glass Transition Temperature” or “Tg” refer to the maximumtemperature that a polycarbonate will retain at least one usefulproperty such as impact resistance, stiffness, strength, or shaperetention. The Tg can be determined by differential scanningcalorimetry.

The term “haze” refers to the percentage of transmitted light, which inpassing through a specimen deviates from the incident beam by forwardscattering. Percent (%) haze may be measured according to ASTM D1003-13.

The term “Melt Volume Rate” (MVR) or “Melt Flow Rate (MFR)” refers tothe flow rate of a polymer in a melt phase as determined using themethod of ASTM D1238-13. MVR is expressed in cubic centimeter per 10minutes, and MFR is expressed in grams per 10 minutes. The higher theMVR or MFR value of a polymer at a specific temperature, the greater theflow of that polymer at that specific temperature.

The term “percent light transmission” or “% T” refers to the ratio oftransmitted light to incident light, and may be measured according toASTM D1003-13.

“Polycarbonate” as used herein refers to an oligomer or a polymercomprising residues of one or more monomers, joined by carbonatelinkages.

The terms “UVA”, “UVB”, “UVC”, and “UVV” as used herein were defined bythe wavelengths of light measured with the radiometer (EIT PowerPuck)used in these studies, as defined by the manufacturer (EIT Inc.,Sterling, Va.). “UV” radiation refers to wavelengths of 200 nanometers(nm) to 450 nm. UVA refers to the range from 320-390 nm, UVB to therange from 280-320 nm, UVC to the range from 250-260 nm, and UVV to therange from 395-445 nm.

The term “crosslink” and its variants refer to the formation of a stablecovalent bond between two polymers/oligomers. This term is intended toencompass the formation of covalent bonds that result in networkformation, or the formation of covalent bonds that result in chainextension. The term “cross-linkable” refers to the ability of apolymer/oligomer to initiate the formation of such stable covalentbonds.

The present disclosure refers to “polymers,” “oligomers”, and“compounds”. A polymer is a large molecule composed of multiplerepeating units chained together. Different molecules of a polymer willhave different lengths, and so a polymer has a molecular weight that isbased on the average value of the molecules (e.g. weight average ornumber average molecular weight). An “oligomer” has only a few repeatingunits, while a “polymer” has many repeating units. In this disclosure,“oligomer” refers to molecules having a weight average molecular weight(Mw) of less than 15,000, and the term “polymer” refers to moleculeshaving an Mw of 15,000 or more, as measured by GPC using polycarbonatemolecular weight standards, measured prior to any UV exposure. In acompound, all molecules have the same molecular weight. Molecularweights are reported herein in Daltons or g/mol.

INTRODUCTION

The present disclosure relates to processes for preparing articles thathave desired properties. The articles are prepared from polymericcompositions comprising a photoactive additive, and optionally one ormore polymeric base resins. More particularly, the photoactive additiveis a cross-linkable polycarbonate resin having a photoactive groupderived from a dihydroxybenzophenone. When the composition is exposed tothe appropriate wavelength(s) of light, cross-linking occurs, whichimproves chemical and flame retardant properties compared to the baseresins alone or to the composition prior to the UV irradiation. Variousparameters of the cross-linkable polycarbonate resin and the polymericcomposition can be varied according to model equations to obtainarticles having desired properties. The cross-linkable polycarbonateresins are first discussed, then blends, then articles, then modelequations for designing the properties of the articles.

Cross-Linkable Polycarbonate Resins

Generally, the photoactive additives (PAA) of the present disclosure arecross-linkable polycarbonate resins that include photoactive ketonegroups that are covalently linked together through one or more dihydroxychain extenders and a carbonate precursor. The term “photoactive” refersto a moiety that, when exposed to ultraviolet light of the appropriatewavelength, crosslinks with another molecule. For example, thebisphenol-A monomer in a bisphenol-A homopolycarbonate is not consideredto be photoactive, even though photo-Fries rearrangement can occur,because the atoms do not crosslink, but merely rearrange in the polymerbackbone. A “ketone group” is a carbonyl group (—CO—) that is bonded totwo other carbon atoms (i.e. —R—CO—R′—). An ester group and a carboxylicacid group are not a ketone group because their carbonyl group is bondedto an oxygen atom.

The photoactive additive is formed from a reaction mixture including atleast a dihydroxybenzophenone, a dihydroxy chain extender, and acarbonate precursor. The dihydroxybenzophenone provides a photoactiveketone group for crosslinking. The carbonate precursor forms carbonatelinkages between the dihydroxy compounds. The reaction product of thismixture is the photoactive additive, which in particular embodiments isa cross-linkable polycarbonate resin. As desired, an end-capping agentand/or additional dihydroxy chain extenders can also be included. Theadditional end-capping agent and the dihydroxy chain extender(s) do nothave photoactive properties.

In particular embodiments, the dihydroxybenzophenone has the structureof Formula (I):

The two hydroxyl groups can be located in any combination of locations,e.g. 4,4′-; 2,2′-; 2,4′-; etc. In more specific embodiments, thedihydroxybenzophenone is 4,4′-dihydroxybenzophenone (4,4′-DHBP).

The cross-linkable polycarbonate resins also include one or moredihydroxy chain extenders (depending on whether a homopolymer, copolymeror terpolymer is desired). The dihydroxy chain extender is a moleculethat contains only two hydroxyl groups. It is contemplated that thedihydroxy chain extender can be a diol or a diacid. The dihydroxy chainextender is not photoactive when exposed to light. The chain extendercan be used to provide a desired level of miscibility when the additiveis mixed with other polymeric resins. The photoactive additive maycomprise from about 75 mole % to about 99.5 mole %, or from 95 mole % toabout 99 mole %, or from about 80 mole % to about 95 mole %, or fromabout 80 mole % to about 90 mole %, of the dihydroxy chain extender.

A first exemplary dihydroxy chain extender is a bisphenol of Formula(A):

wherein R^(a) and R^(b) each represent a halogen atom or a monovalenthydrocarbon group and may be the same or different; p and q are eachindependently integers of 0 to 4; and A represents one of the groups ofFormula (A-1):

wherein R^(c) and R^(d) each independently represent a hydrogen atom ora monovalent linear or cyclic hydrocarbon group; R^(e) is a divalenthydrocarbon group; R^(f) is a monovalent linear hydrocarbon group; and ris an integer from 0 to 5. For example, A can be a substituted orunsubstituted C₃-C₁₈ cycloalkylidene.

Specific examples of the types of bisphenol compounds that may berepresented by Formula (A) include 2,2-bis(4-hydroxyphenyl) propane(“bisphenol-A” or “BPA”), 4,4′-(1-phenylethane-1,1-diyl)diphenol or1,1-bis(4-hydroxyphenyl)-1-phenylethane (bisphenol-AP);1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane) (bisphenol TMC);1,1-bis(4-hydroxy-3-methylphenyl) cyclohexane (DMBPC); and2,2-bis(3,5-dibromo-4-hydroxyphenyl) propane (tetrabromobisphenol-A orTBBPA).

A second exemplary dihydroxy chain extender is a bisphenol of Formula(B):

wherein each R^(k) is independently a C₁₋₁₀ hydrocarbon group, and n is0 to 4. The halogen is usually bromine. Examples of compounds that maybe represented by Formula (B) include resorcinol, 5-methyl resorcinol,5-phenyl resorcinol, catechol; hydroquinone; and substitutedhydroquinones such as 2-methyl hydroquinone.

A third exemplary dihydroxy chain extender is abisphenolpolydiorganosiloxane of Formula (C-1) or (C-2):

wherein each Ar is independently aryl; each R is independently alkyl,alkoxy, alkenyl, alkenyloxy, aryl, aryloxy, arylalkyl, or alkylaryl;each R₆ is independently a divalent C₁-C₃₀ organic group such as aC₁-C₃₀ alkyl, C₁-C₃₀ aryl, or C₁-C₃₀ alkylaryl; and D and E are anaverage value of 2 to about 1000, including from about 2 to about 500,or about 10 to about 200, or more specifically about 10 to about 75.

Specific examples of Formulas (C-1) and (C-2) are illustrated below asFormulas (C-a) through (C-d):

where E is an average value from 10 to 200.

A fourth exemplary dihydroxy chain extender is an aliphatic diol ofFormula (D):

wherein each X is independently hydrogen, halogen, or alkyl; and j is aninteger from 1 to 20. Examples of an aliphatic diol include ethyleneglycol, propanediol, 2,2-dimethyl-propanediol, 1,6-hexanediol, and1,12-dodecanediol.

A fifth exemplary dihydroxy chain extender is a dihydroxy compound ofFormula (E), which may be useful for high heat applications:

wherein R¹³ and R¹⁵ are each independently halogen or C₁-C₆ alkyl, R¹⁴is C₁-C₆ alkyl, or phenyl substituted with up to five halogens or C₁-C₆alkyl groups, and c is 0 to 4. In specific embodiments, R¹⁴ is a C₁-C₆alkyl or phenyl group; or each c is 0. Compounds of Formula (E) include3,3-bis(4-hydroxyphenyl)-2-phenylisoindolin-1-one (PPPBP).

Another dihydroxy chain extender that might impart high Tgs to thepolycarbonate has adamantane units. Such compounds may have repetitiveunits of the following formula (F) for high heat applications:

wherein R₁ is halogen, C₁-C₆ alkyl, C₁-C₆ alkoxy, C₆-C₁₂ aryl, C₇-C₁₃aryl-substituted alkenyl, or C₁-C₆ fluoroalkyl; R₂ is halogen, C₁-C₁₂alkyl, C₁-C₁₂ alkoxy, C₆-C₁₂ aryl, C₇-C₁₃ aryl-substituted alkenyl, orC₁-C₁₂ fluoroalkyl; m is an integer of 0 to 4; and n is an integer of 0to 14.

Another dihydroxy compound that might impart high Tgs to thepolycarbonate is a fluorene-unit containing dihydroxy compoundrepresented by the following Formula (G):

wherein R₁ to R₄ are each independently hydrogen, C₁-C₉ hydrocarbon, orhalogen.

Another dihydroxy chain extender that could be used is an isosorbide. Amonomer unit derived from isosorbide may be an isorbide-bisphenol unitof Formula (H):

wherein R₁ is an isosorbide unit and R₂-R₉ are each independently ahydrogen, a halogen, a C₁-C₆ alkyl, a methoxy, an ethoxy, or an alkylester.

The R₁ isosorbide unit may be represented by Formula (H-a):

The isosorbide unit may be derived from one isosorbide, or be a mixtureof isomers of isosorbide. The stereochemistry of Formula (I) is notparticularly limited. These diols may be prepared by the dehydration ofthe corresponding hexitols. The isosorbide-bisphenol may have a pKa ofbetween 8 and 11.

While the compounds of Formulas (A)-(H) are diols, diacids may also beused as the dihydroxy chain extender. Some exemplary diacids includethose having the structures of one of Formulas (1)-(2):

where Y is hydroxyl, halogen, alkoxy, or aryloxy; and where n is 1 to20. It should be noted that Formula (1) encompasses adipic acid (n=4),sebacic acid (n=8), and dodecanedioic acid (n=10). Similarly, Formula(2) encompasses isophthalic acid and terephthalic acid. When diacids areused, the crosslinkable polycarbonate of the present disclosure may be apolyester-polycarbonate. The molar ratio of ester units to carbonateunits in the polyester-polycarbonate may be 1:99 to 99:1, specifically10:90 to 90:10, more specifically 25:75 to 75:25.

The reaction mixture used to form the cross-linkable polycarbonateresins of the present disclosure also includes a carbonate precursor.The carbonate precursor serves as a carbonyl source. In particular, thecarbonate precursor may be phosgene, or may be a diaryl carbonate.Exemplary diaryl carbonates include for example diphenyl carbonate(DPC), ditolyl carbonate, bis(chlorophenyl) carbonate, m-cresylcarbonate, and dinaphthyl carbonate, and are used in melt polymerizationprocesses. In interfacial polymerization processes, phosgene andcarbonyl halides are usually selected as the carbonate precursor.

Particularly contemplated for use in the processes of the presentdisclosure are phosgene and diphenyl carbonate (DPC), which areillustrated below as Formulas (3) and (4), respectively:

The molar ratio of the benzophenone to the dihydroxy chain extender(s)can be from 1:1 to 1:200 prior to UV exposure, including from 1:2 to1:200, or from about 1:99 to about 3:97, or from about 1:99 to about6:94, or from about 10:90 to about 25:75 or from about 1:3 to about1:200.

If desired, the reaction mixture can include branching agents thatcontain three, four, or even more functional groups. The functionalgroups can be, for example, hydroxyl groups or carboxylic acid groups.Generally speaking, these react in the same way as the dihydroxy chainextender. Branching agents with three hydroxyl groups include1,1,1-trimethoxyethane; 1,1,1-trimethoxymethane; 1,1,1-tris(hydroxyphenyl) ethane (TH PE), and1,3,5-tris[2-(4-hydroxyphenyl)-propan-2-yl]benzene. Branching agentswith four hydroxyl groups include pentaerythritol and4-[2,6,6-tris(4-hydroxyphenyl)heptan-2-yl]phenol. In other embodiments,the branching agent can be an oligomer, made from epoxidized novolacmonomer, that permits the desired number of functional groups to beprovided.

Branching agents having three carboxylic acid groups includebenzenetricarboxylic acid, citric acid, and cyanuric chloride. Branchingagents having four carboxylic acid groups include benzenetetracarboxylicacid, biphenyl tetracarboxylic acid, and benzophenone tetracarboxylicdianhydride. The corresponding acyl halides and esters of such acids arealso contemplated. Oligomers containing glycidyl methacrylate monomerswith styrene or methacrylate monomers are also contemplated.

An end-capping agent is generally used to terminate any polymer chainsof the photoactive additive. The end-capping agent (i.e. chain stopper)can be a monohydroxy compound, a mono-acid compound, or a mono-estercompound. Exemplary endcapping agents include phenol, p-cumylphenol(PCP), resorcinol monobenzoate, p-tert-butylphenol, octylphenol,p-cyanophenol, and p-methoxyphenol. Unless modified with otheradjectives, the term “end-capping agent” is used herein to denote acompound that is not photoactive when exposed to light. For example, theend-capping agent does not contain a ketone group. The photoactiveadditive may comprise about 0.5 mole % to about 5.0 mole % endcap groupsderived from each end-capping agent, including about 1 mole % to about 3mole %, or from about 1.7 mole % to about 2.5 mole %, or from about 2mole % to about 2.5 mole %, or from about 2.5 mole % to about 3.0 mole %endcap groups derived from each end-capping agent.

The cross-linkable polycarbonate resins of the present disclosure can bean oligomer or a polymer. The oligomer has a weight average molecularweight (Mw) of less than 15,000, including 10,000 or less. The polymericpolycarbonates of the present disclosure have a Mw of 15,000 or higher.In particular embodiments, the Mw is between 17,000 and 80,000 Daltons,or between 17,000 and 35,000 Daltons. These molecular weights aremeasured prior to any UV exposure. The Mw may be varied as desired. Insome particular embodiments, the Mw of the photoactive additives isabout 5,000 or less.

One example of a photoactive additive is a cross-linkable polycarbonateresin shown in FIG. 1. Here, 4,4′-dihydroxybenzophenone is reacted withphosgene (carbonate precursor), bisphenol-A (dihydroxy chain extender),and p-cumylphenol (end-capping agent) to obtain the cross-linkablepolycarbonate resin. A copolymer is thus formed with a weight averagemolecular weight and a polydispersity index, and containing carbonatelinkages.

FIG. 2 illustrates the formation of a branched cross-linkablepolycarbonate. As illustrated here, 4,4′-dihydroxybenzophenone isreacted with phosgene (carbonate precursor), bisphenol-A (dihydroxychain extender), p-cumylphenol (end-capping agent), and a branchingagent (1,1,1-tris-hydroxyphenylethane (THPE)). A copolymer is thusformed.

One crosslinking mechanism of the photoactive additives is believed tobe due to hydrogen abstraction by the ketone group from an alkyl groupthat acts as a hydrogen donor and subsequent coupling of the resultingradicals. This mechanism is illustrated in FIG. 3 with reference to abenzophenone (the photoactive moiety) and a bisphenol-A (BPA) monomer.Upon exposure to UV, the oxygen atom of the benzophenone abstracts ahydrogen atom from a methyl group on the BPA monomer and becomes ahydroxyl group. The methylene group then forms a covalent bond with thecarbon of the ketone group. Put another way, the ketone group of thebenzophenone could be considered to be a photoactive group. It should benoted that the presence of hydrogen is critical for this reaction tooccur. Other mechanisms may occur after the initial abstraction eventwith base resins containing unsaturated bonds or reactive side groups.

The cross-linkable polycarbonate resin contains repeating units derivedfrom a dihydroxybenzophenone monomer (i.e. of Formula (I)). Thecross-linkable polycarbonate resin may comprise from about 0.5 mole % toabout 50 mole % of repeating units derived from thedihydroxybenzophenone. In more particular embodiments, thecross-linkable polycarbonate resin comprises from about 1 mole % toabout 3 mole %, or from about 1 mole % to about 5 mole %, or from about1 mole % to about 6 mole %, or from about 5 mole % to about 20 mole %,or from about 10 mole % to about 20 mole %, or from about 0.5 mole % toabout 25 mole % of repeating units derived from thedihydroxybenzophenone.

In more specific embodiments, the photoactive cross-linkablepolycarbonate resin is a terpolymer formed from the reaction of adihydroxybenzophenone, a first dihydroxy chain extender, a seconddihydroxy chain extender, a carbonate precursor, and optionally one ormore end-capping agents. The terpolymer contains from about 0.5 mole %to 50 mole % of repeating units derived from the dihydroxybenzophenone,from about 50 mole % to 99.5 mole % of repeating units derived from thefirst dihydroxy chain extender, and from about 50 mole % to 99.5 mole %of repeating units derived from the second dihydroxy chain extender.Most desirably, the dihydroxybenzophenone is 4,4′-dihydroxybenzophenone(4,4′-DHBP). Usually, the first dihydroxy chain extender is bisphenol-A.In particular embodiments, the cross-linkable polycarbonate terpolymerdoes not have photoactive endcaps.

Specific examples of contemplated terpolymers include those including asmonomers (i) DHBP; (ii) bisphenol-A; and (iii) a third monomer selectedfrom the group consisting of sebacic acid, a polysiloxane monomer,DMBPC, or tetrabromobisphenol-A.

In other specific embodiments, the photoactive cross-linkablepolycarbonate resin is a copolymer formed from the reaction of adihydroxybenzophenone, a first dihydroxy chain extender, a carbonateprecursor, and optionally one or more end-capping agents. The copolymercontains from about 0.5 mole % to 50 mole % of repeating units derivedfrom the dihydroxybenzophenone, and from about 50 mole % to 99.5 mole %of repeating units derived from the first dihydroxy chain extender. Mostdesirably, the dihydroxybenzophenone is 4,4′-dihydroxybenzophenone. Inparticular embodiments, the cross-linkable polycarbonate copolymer doesnot have photoactive endcaps. Specific examples of contemplatedcopolymers include a copolymer having as monomers (i) 4,4′-DHBP and (ii)bisphenol-A.

These polycarbonates, prior to cross-linking, can be provided asthermally stable high melt-flow polymers, and can thus be used tofabricate a variety of thin-walled articles (e.g., 3 mm or less). Thesearticles are subsequently exposed to ultraviolet radiation to affectcross-linking. The cross-linked materials, in addition to flameresistance and chemical resistance, may retain or exhibit superiormechanical properties (e.g., impact resistance, ductility) as comparedto the polycarbonate resin prior to cross-linking.

The cross-linkable polycarbonates of the present disclosure may have aglass transition temperature (Tg) of greater than 120° C., 125° C., 130°C., 135° C., 140° C., 145° C., 150° C., 155° C., 160° C., 165° C., 170°C., 175° C., 180° C., 185° C., 190° C., 200° C., 210° C., 220° C., 230°C., 240° C., 250° C., 260° C., 270° C., 280° C., 290° C., or 300° C., asmeasured using a differential scanning calorimetry method. In certainembodiments, the polycarbonates have glass transition temperaturesranging from about 120° C. to about 230° C., about 140° C. to about 160°C., about 145° C. to about 155° C., about 148° C. to about 152° C., orabout 149° C. to about 151° C.

The cross-linkable polycarbonates of the present disclosure may have aweight average molecular weight (Mw) of 15,000 to about 80,000 Daltons[±1,000 Daltons], or of 15,000 to about 35,000 Daltons [±1,000 Daltons],or of about 20,000 to about 30,000 Daltons [±1,000 Daltons], or of17,000 to about 80,000 Daltons. Molecular weight determinations may beperformed using gel permeation chromatography (GPC), using across-linked styrene-divinylbenzene column and calibrated topolycarbonate references using a UV-VIS detector set at 264 nm. Samplesmay be prepared at a concentration of about 1 milligram per milliliter(mg/ml), and eluted at a flow rate of about 1.0 milliliter per minute(ml/min).

The cross-linkable polycarbonates of the present disclosure may have apolydispersity index (PDI) of about 2.0 to about 5.0, about 2.0 to about3.0, or about 2.0 to about 2.5. The PDI is measured prior to any UVexposure.

The cross-linkable polycarbonates of the present disclosure may have amelt flow rate (MFR) of 1 to 45 grams/10 min, 6 to 15 grams/10 min, 6 to8 grams/10 min, 6 to 12 grams/10 min, 2 to 30 grams/10 min, 5 to 30grams/10 min, 8 to 12 grams/10 min, 8 to 10 grams/10 min, or 20 to 30grams/10 min, using the ASTM D1238-13 method, 1.2 kg load, 300° C.temperature, 360 second dwell.

The cross-linkable polycarbonates of the present disclosure may have abiocontent of 2 wt % to 90 wt %; 5 wt % to 25 wt %; 10 wt % to 30 wt %;15 wt % to 35 wt %; 20 wt % to 40 wt %; 25 wt % to 45 wt %; 30 wt % to50 wt %; 35 wt % to 55 wt %; 40 wt % to 60 wt %; 45 wt % to 65 wt %; 55wt % to 70% wt %; 60 wt % to 75 wt %; 50 wt % to 80 wt %; or 50 wt % to90 wt %. The biocontent may be measured according to ASTM D6866-10.

The cross-linkable polycarbonates of the present disclosure may have amodulus of elasticity of greater than or equal to (≧) 2200 megapascals(MPa), ≧2310 MPa, ≧2320 MPa, ≧2330 MPa, ≧2340 MPa, ≧2350 MPa, ≧2360 MPa,≧2370 MPa, ≧2380 MPa, ≧2390 MPa, ≧2400 MPa, ≧2420 MPa, ≧2440 MPa, ≧2460MPa, ≧2480 MPa, ≧2500 MPa, or ≧2520 MPa as measured by ASTM D790-10 at1.3 mm/min, 50 mm span.

In embodiments, the cross-linkable polycarbonates of the presentdisclosure may have a flexural modulus of 2,200 to 2,500, preferably2,250 to 2,450, more preferably 2,300 to 2,400 MPa. In otherembodiments, the cross-linkable polycarbonates of the present disclosuremay have a flexural modulus of 2,300 to 2,600, preferably 2,400 to2,600, more preferably 2,450 to 2,550 MPa. The flexural modulus is alsomeasured by ASTM D790-10.

The cross-linkable polycarbonates of the present disclosure may have atensile strength at break of greater than or equal to (≧) 60 megapascals(MPa), ≧61 MPa, ≧62 MPa, ≧63 MPa, ≧64 MPa, ≧65 MPa, ≧66 MPa, ≧67 MPa,≧68 MPa, ≧69 MPa, ≧70 MPa, ≧71 MPa, ≧72 MPa, ≧73 MPa, ≧74 MPa, ≧75 MPaas measured by ASTM D638-10 Type I at 50 mm/min.

The cross-linkable polycarbonates of the present disclosure may possessa ductility of greater than or equal to (≧) 60%, ≧65%, ≧70%, ≧75%, ≧80%,≧85%, ≧90%, ≧95%, or 100% in a notched izod test at −20° C., −15° C.,−10° C., 0° C., 5° C., 10° C., 15° C., 20° C., 23° C., 25° C., 30° C.,or 35° C. at a thickness of 3.2 mm according to ASTM D256-10.

The cross-linkable polycarbonates of the present disclosure may have anotched Izod impact strength (NII) of ≧500 Joules per meter (J/m), ≧550J/m, ≧600 J/m, ≧650 J/m, ≧700 J/m, ≧750 J/m, ≧800 J/m, ≧850 J/m, ≧900J/m, ≧950 J/m, or ≧1000 J/m, measured at 23° C. according to ASTMD256-10.

The cross-linkable polycarbonates of the present disclosure may have aheat distortion temperature of greater than or equal to 110° C., 111°C., 112° C., 113° C., 114° C., 115° C., 116° C., 117° C., 118° C., 119°C., 120° C., 121° C., 122° C., 123° C., 124° C., 125° C., 126° C., 127°C., 128° C., 129° C., 130° C., 131° C., 132° C., 133° C., 134° C., 135°C., 136° C., 137° C., 138° C., 139° C., 140° C., 141° C., 142° C., 143°C., 144° C., 145° C., 146° C., 147° C., 148° C., 149° C., 150° C., 151°C., 152° C., 153° C., 154° C., 155° C., 156° C., 157° C., 158° C., 159°C., 160, 161° C., 162° C., 163° C., 164° C., 165° C., 166° C., 167° C.,168° C., 169° C., or 170° C., as measured according to ASTM D648-07 at1.82 MPa, with 3.2 mm thick unannealed mm bar.

The cross-linkable polycarbonates of the present disclosure may have apercent haze value of less than or equal to (≦) 10.0%, ≦8.0%, ≦6.0%,≦5.0%, ≦4.0%, ≦3.0%, ≦2.0%, ≦1.5%, ≦1.0%, or ≦0.5% as measured at acertain thickness according to ASTM D1003-13. The polycarbonate haze maybe measured at a 2.0, 2.2, 2.4, 2.54, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8,or a 4.0 millimeter thickness. The polycarbonate may be measured at a0.125 inch thickness.

The polycarbonate may have a light transmittance greater than or equalto (≧) 50%, ≧60%, ≧65%, ≧70%, ≧75%, ≧80%, ≧85%, ≧90%, ≧95%, ≧96%, ≧97%,≧98%, ≧99%, ≧99.1%, ≧99.2%, ≧99.3%, ≧99.4%, ≧99.5%, ≧99.6%, ≧99.7%,≧99.8%, or ≧99.9%, as measured at certain thicknesses according to ASTMD1003-13. The polycarbonate transparency may be measured at a 2.0, 2.2,2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, or a 4.0 millimeter thickness.

In certain embodiments, the cross-linkable polycarbonates of the presentdisclosure do not include soft block or soft aliphatic segments in thepolycarbonate chain. For example, the following aliphatic soft segmentsthat may be excluded from the cross-linkable polycarbonates of thepresent disclosure include aliphatic polyesters, aliphatic polyethers,aliphatic polythioeithers, aliphatic polyacetals, aliphaticpolycarbonates, C—C linked polymers and polysiloxanes. The soft segmentsof aliphatic polyesters, aliphatic polyethers, aliphaticpolythioeithers, aliphatic polyacetals, aliphatic polycarbonates may becharacterized as having number average molecular weight (Mns) of greaterthan 600 Daltons.

Processes

An interfacial polycondensation polymerization process for bisphenol-A(BPA) based polycarbonates can be used to prepare the cross-linkablepolycarbonates of the present disclosure. Although the reactionconditions for interfacial polymerization can vary, an exemplary processgenerally involves dissolving or dispersing one or more dihydric phenolreactants (e.g. bisphenol-A) in water, adding the resulting mixture to awater-immiscible solvent medium, and contacting the reactants with acarbonate precursor (e.g. phosgene) in the presence of a catalyst (e.g.triethylamine, TEA) and an acid acceptor such as an alkali metalhydroxide.

Four different processes are disclosed herein for producing someembodiments of the photoactive additive which contain carbonatelinkages. Each process includes the following ingredients: one or moredihydroxy chain extenders, an end-capping agent, a carbonate precursor,a base, a tertiary amine catalyst, water, and a water-immiscible organicsolvent. It should be noted that more than one of each ingredient can beused to produce the crosslinkable polycarbonates. Some information oneach ingredient is first provided below.

A hydroxybenzophenone is present as the photoactive moiety, and can bepresent either as the end-capping agent (i.e. monohydroxybenzophenone)or as a diol (i.e. dihydroxybenzophenone). In the process descriptionsbelow, reference will be made to dihydroxy compounds, which should beconstrued as including the dihydroxy chain extender and adihydroxybenzophenone monomer. Reference will also be made to theend-capping agent, which should be construed as including amonohydroxybenzophenone.

The dihydroxy chain extender may have the structure of any one ofFormulas (A)-(H) or (1)-(2), and include monomers such as bisphenol-A.

Examples of end-capping agents (other than the monohydroxybenzophenone)include phenol, p-cumylphenol (PCP), p-tert-butylphenol, octylphenol,and p-cyanophenol.

The carbonate precursor may be, for example, a carbonyl halide such ascarbonyl dibromide or carbonyl dichloride (also known as phosgene), or ahaloformate such as a bishaloformate of a dihydric phenol (e.g., thebischloroformate of bisphenol-A, hydroquinone, or the like) or a glycol(e.g., the bishaloformate of ethylene glycol, neopentyl glycol,polyethylene glycol, or the like). Combinations comprising at least oneof the foregoing types of carbonate precursors can also be used. Incertain embodiments, the carbonate precursor is phosgene, a triphosgene,diacyl halide, dihaloformate, dicyanate, diester, diepoxy,diarylcarbonate, dianhydride, diacid chloride, or any combinationthereof. An interfacial polymerization reaction to form carbonatelinkages may use phosgene as a carbonate precursor, and is referred toas a phosgenation reaction. The compounds of Formulas (3) or (4) arecarbonate precursors.

The base is used for the regulation of the pH of the reaction mixture.In particular embodiments, the base is an alkali metal hydroxide, suchas sodium hydroxide (NaOH) or potassium hydroxide (KOH).

A tertiary amine catalyst is used for polymerization. Exemplary tertiaryamine catalysts that can be used are aliphatic tertiary amines such astriethylamine (TEA)), N-ethylpiperidine, 1,4-diazabicyclo[2.2.2]octane(DABCO), tributylamine, cycloaliphatic amines such asN,N-diethyl-cyclohexylamine and aromatic tertiary amines such asN,N-dimethylaniline.

Sometimes, a phase transfer catalyst is also used. Among the phasetransfer catalysts that can be used are catalysts of the formula(R³⁰)₄Q⁺X, wherein each R³⁰ is the same or different, and is a C₁-C₁₀alkyl group; Q is a nitrogen or phosphorus atom; and X is a halogenatom, C₁-C₈ alkoxy group, or C₆-C₁₈ aryloxy group. Exemplary phasetransfer catalysts include, for example, [CH₃(CH₂)₃]₄NX, [CH₃(CH₂)₃]₄PX,[CH₃(CH₂)₅]₄NX, [CH₃(CH₂)₆]₄NX, [CH₃(CH₂)₄]₄NX, CH₃[CH₃(CH₂)₃]₃NX, andCH₃[CH₃(CH₂)₂]₃NX, wherein X is Cl⁻, Br⁻, a C₁-C₈ alkoxy group or aC₆-C₁₈ aryloxy group, such as methyltributylammonium chloride.

The most commonly used water-immiscible solvents include methylenechloride, 1,2-dichloroethane, chlorobenzene, toluene, and the like.

In the first process, sometimes referred to as the “upfront” process,the diol(s), end-capping agent, catalyst, water, and water-immisciblesolvent are combined upfront in a vessel to form a reaction mixture. Thereaction mixture is then exposed to the carbonate precursor, for exampleby phosgenation, while the base is co-added to regulate the pH, toobtain the photoactive additive.

The pH of the reaction mixture is usually from about 8.5 to about 10,and can be maintained by using a basic solution (e.g. aqueous NaOH). Thereaction mixture is then charged with the carbonate precursor, which isusually phosgene. The carbonate precursor is added to the reactionmixture over a period of about 15 minutes to about 45 minutes. While thecarbonate precursor is being added, the pH is also maintained in therange of about 8.5 to about 10, again by addition of a basic solution asneeded. The cross-linkable polycarbonate is thus obtained, and is thenisolated from the reaction mixture.

In the second process, also known as the “solution addition” process,the diol(s), tertiary amine catalyst, water, and water-immisciblesolvent are combined in a vessel to form a reaction mixture. The totalcharge of the carbonate precursor is then added to this reaction mixturein the vessel over a total time period, while the base is co-added toregulate the pH. The carbonate precursor is first added to the reactionmixture along with the base to regulate the pH for a first time period.After the first time period ends, the end-capping agent is added in acontrolled manner to the reaction mixture, also referred to asprogrammed addition. The addition of the end-capping agent occurs for asecond time period after the first time period, rather than as a bolusat the beginning of the reaction (as in the upfront process). Thecarbonate precursor and the base are also added concurrently with theend-capping agent during the second time period. After the second timeperiod ends, the remainder of the carbonate precursor continuesuninterrupted for a third time period until the total charge is reached.The base is also co-added during the third time period to regulate thereaction pH. The pH of the reaction mixture is usually from about 8.5 toabout 10, and can be maintained by using a basic solution (e.g. aqueousNaOH, made from the base). The end-capping agent is not added duringeither the first time period or the third time period. The photoactiveadditive is thus obtained. The main difference between the first andsecond processes is in the addition of the end-capping agent over time.

In the second process, the carbonate precursor is added to the reactionmixture over a total time period, which may be for example from about 15minutes to about 45 minutes. The total time period is the durationneeded to add the total charge of the carbonate precursor (measuredeither by weight or by moles) to the reaction mixture. It iscontemplated that the carbonate precursor is added at a constant rateover the total time period. The carbonate precursor is first added tothe reaction mixture along with the base to regulate the pH for a firsttime period, ranging from about 2 minutes to about 20 minutes. Then,during a second time period, the end-capping agent is added to thereaction mixture concurrently with the carbonate precursor and the base.It is contemplated that the end-capping agent is added at a constantrate during this second time period, which can range from about 1 minuteto about 5 minutes. After the second time period ends, the remainingcarbonate precursor is charged to the reaction mixture for a third timeperiod, along with the base to regulate the reaction pH. Thecross-linkable polycarbonate is thus obtained, and is then isolated fromthe reaction mixture.

The total time period for the reaction is the sum of the first timeperiod, the second time period, and the third time period. In particularembodiments, the second time period in which the solution containing theend-capping agent is added to the reaction mixture begins at a pointbetween 10% to about 40% of the total time period. Put another way, thefirst time period is 10% of the total time period.

For example, if 2400 grams of phosgene were to be added to a reactionmixture at a rate of 80 g/min, and 500 ml of a PCP solution were to beadded to the reaction mixture at a rate of 500 ml/min after an initialcharge of 240 grams of phosgene, then the total time period would be 30minutes, the first time period would be three minutes, the second timeperiod would be one minute, and the third period would be 26 minutes.

The third process is also referred to as a bis-chloroformate orchlorofomate (BCF) process. Chloroformate oligomers are prepared byreacting a carbonate precursor, specifically phosgene, with the diol(s)in the absence of the tertiary amine catalyst, while the base isco-added to regulate the pH. The chloroformate oligomers can contain amixture of monochloroformates, bischloroformates, and bisphenolterminated oligomers. After the chloroformate oligomers are generated,the phosgene can optionally be allowed to substantially condense orhydrolyze, then the end-capping agent is added to the chloroformatemixture. The reaction is allowed to proceed, and the tertiary aminecatalyst is added to complete the reaction. The pH of the reactionmixture is usually from about 8.5 to about 10 prior to the addition ofthe phosgene. During the addition of the phosgene, the pH is maintainedbetween about 6 and about 8, by using a basic solution (e.g. aqueousNaOH).

The fourth process uses a tubular reactor. In the tubular reactor, theend-capping agent is pre-reacted with a carbonate precursor(specifically phosgene) to form chloroformates. The water-immisciblesolvent is used as a solvent in the tubular reactor. In a separatereactor, the diol(s), tertiary amine catalyst, water, andwater-immiscible solvent are combined to form a reaction mixture. Thechloroformates in the tubular reactor are then fed into the reactor overa first time period along with additional carbonate precursor tocomplete the reaction while the base is co-added to regulate the pH.During the addition of the chloroformates, the pH is maintained betweenabout 8.5 and about 10, by using a basic solution (e.g. aqueous NaOH).

The resulting cross-linkable polycarbonate formed by any of theseprocesses contains only a small amount of low-molecular-weightcomponents. This can be measured in two different ways: the level ofdiarylcarbonates (DAC) and the lows percentage can be measured.Diarylcarbonates are formed by the reaction of two end-capping agentswith phosgene, creating a small molecule. In embodiments, the resultingphotoactive additive contains less than 1000 ppm of diarylcarbonates.The lows percentage is the percentage by weight of oligomeric chainshaving a molecular weight of less than 1000. In embodiments, the lowspercentage is 2.0 wt % or less, including from about 1.0 wt % to 2.0 wt%. The DAC level and the lows percentage can be measured by highperformance liquid chromatography (HPLC) or gel permeationchromatography (GPC). Also of note is that the resulting photoactiveadditive does not contain any residual pyridine, because pyridine is notused in the manufacture of the photoactive additive.

Blends with Second Polymer Resin

The photoactive additive can be blended with a polymeric base resin thatis different from the photoactive additive, i.e. a second polymer resin,to form the polymeric compositions/blends of the present disclosure.More specifically, the second polymer resin does not contain photoactivegroups. In embodiments, the weight ratio of the cross-linkablepolycarbonate resin to the polymeric base resin is from 1:99 to 99:1.The weight ratio of the cross-linkable polycarbonate resin to thepolymeric base resin may be from about 50:50 to about 95:5, or fromabout 10:90 to about 85:15, or from about 25:75 to about 50:50. Thepolymeric base resin has, in specific embodiments, a weight-averagemolecular weight of about 21,000 or greater, including from about 21,000to about 40,000.

The cross-linkable polycarbonate resins are suitable for blending withpolycarbonate homopolymers, polycarbonate copolymers, and polycarbonateblends. They are also suitable for blending with polyesters,polyarylates, polyestercarbonates, and polyetherimides.

The blends may comprise one or more distinct cross-linkablepolycarbonates, as described herein, and/or one or more cross-linkedpolycarbonate(s). The blends also comprise one or more additionalpolymers. The blends may comprise additional components, such as one ormore additives. In certain embodiments, a blend comprises across-linkable and/or cross-linked polycarbonate (Polymer A) and asecond polymer (Polymer B), and optionally one or more additives. Inanother embodiment, a blend comprises a combination of a cross-linkableand/or cross-linked polycarbonate (Polymer A); and a secondpolycarbonate (Polymer B), wherein the second polycarbonate is differentfrom the first polycarbonate.

The second polymer (Polymer B) may be any polymer different from thefirst polymer that is suitable for use in a blend composition. Incertain embodiments, the second polymer may be a polyester, apolyestercarbonate, a bisphenol-A homopolycarbonate, a polycarbonatecopolymer, a tetrabromobisphenol-A polycarbonate copolymer, apolysiloxane-co-bisphenol-A polycarbonate, a polyesteramide, apolyimide, a polyetherimide, a polyamideimide, a polyether, apolyethersulfone, a polyepoxide, a polylactide, a polylactic acid (PLA),or any combination thereof.

In certain embodiments, the polymeric base resin may be a vinyl polymer,a rubber-modified graft copolymer, an acrylic polymer,polyacrylonitrile, a polystyrene, a polyolefin, a polyester, apolyesteramide, a polysiloxane, a polyurethane, a polyamide, apolyamideimide, a polysulfone, a polyepoxide, a polyether, a polyimide,a polyetherimide, a polyphenylene ether, a polyphenylene sulfide, apolyether ketone, a polyether ether ketone, anacrylonitrile-butadiene-styrene (ABS) resin, anacrylic-styrene-acrylonitrile (ASA) resin, a polyethersulfone, apolyphenylsulfone, a poly(alkenylaromatic) polymer, a polybutadiene, apolyacetal, a polycarbonate, a polyphenylene ether, an ethylene-vinylacetate copolymer, a polyvinyl acetate, a liquid crystal polymer, anethylene-tetrafluoroethylene copolymer, an aromatic polyester, apolyvinyl fluoride, a polyvinylidene fluoride, a polyvinylidenechloride, tetrafluoroethylene, a polylactide, a polylactic acid (PLA), apolycarbonate-polyorganosiloxane block copolymer, or a copolymercomprising: (i) an aromatic ester, (ii) an estercarbonate, and (iii)carbonate repeat units. The blend composition may comprise additionalpolymers (e.g. a third, fourth, fifth, sixth, etc., polymer).

In certain embodiments, the polymeric base resin may be ahomopolycarbonate, a copolycarbonate, a polycarbonate-polysiloxanecopolymer, a polyester-polycarbonate, or any combination thereof. Incertain embodiments, the polymeric base resin is a p-cumyl phenol cappedpoly(isophthalate-terephthalate-resorcinol ester)-co-(bisphenol-Acarbonate) copolymer. In certain embodiments, the polymeric base resinis a polycarbonate-polysiloxane copolymer.

The p-cumyl phenol capped poly(isophthalate-terephthalate-resorcinolester)-co-(bisphenol-A carbonate) polymer or apolycarbonate-polysiloxane copolymer may have a polysiloxane contentfrom 0.4 wt % to 25 wt %. In one preferred embodiment, the polymericbase resin is a p-cumylphenol capped poly(19 mole %isophthalate-terephthalate-resorcinol ester)-co-(75 mole % bisphenol-Acarbonate)-co-(6 mole % resorcinol carbonate) copolymer (Mw=29,000Daltons). In another preferred embodiment, the polymeric base resin is ap-cumylphenol capped poly(10 wt % isophthalate-terephthalate-resorcinolester)-co-(87 wt % bisphenol-A carbonate)-co-(3 mole % resorcinolcarbonate) copolymer (Mw=29,000 Daltons).

In another preferred embodiment, the polymeric base resin is apolycarbonate polysiloxane copolymer. The polycarbonate-polysiloxanecopolymer may be a siloxane block co-polycarbonate comprising from about4 wt % siloxane (±10%) to about 25 wt % siloxane (±10%) and having asiloxane chain length of 10 to 200. In another preferred embodiment, thepolymeric base resin is a PC-siloxane copolymer with 20% siloxanesegments by weight.

In another preferred embodiment, the polymeric base resin is ap-cumylphenol capped poly(65 mole % BPA carbonate)-co-(35 mole %3,3-bis(4-hydroxyphenyl)-2-phenylisoindolin-1-one (PPPBP) carbonate)copolymer (Mw=25,000 Daltons).

In another preferred embodiment, the polymeric base resin is apolyphosphonate polymer, a polyphosphonate copolymer, or apoly(polyphosphonate)-co-(BPA carbonate) copolymer.

In yet other embodiments, the polymer resin in the blend is selectedfrom the group consisting of a polycarbonate-polysiloxane copolymer; apolycarbonate resin having an aliphatic chain containing at least twocarbon atoms as a repeating unit in the polymer backbone; a copolyesterpolymer; a bisphenol-A homopolycarbonate; a polystyrene polymer; apoly(methyl methacrylate) polymer; a thermoplastic polyester; apolybutylene terephthalate polymer; a methylmethacrylate-butadiene-styrene copolymer; anacrylonitrile-butadiene-styrene copolymer; a dimethyl bisphenolcyclohexane-co-bisphenol-A copolymer; a polyetherimide; apolyethersulfone; and a copolycarbonate of bisphenol-A and1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane) (BPTMC).

In particular embodiments, the polymer resin in the blend is apolycarbonate-polysiloxane (PC—Si) copolymer. The polycarbonate units ofthe copolymer are derived from dihydroxy compounds having the structuresof any of the formulas described above, but particularly those of thechain extenders of Formulas (A) and (B). Some illustrative examples ofsuitable dihydroxy compounds include the following:1,1-bis(4-hydroxyphenyl) methane, 1,1-bis(4-hydroxyphenyl) ethane,2,2-bis(4-hydroxyphenyl) propane (hereinafter “bisphenol-A” or “BPA”),2,2-bis(4-hydroxyphenyl) butane, 2,2-bis(4-hydroxyphenyl) octane,1,1-bis(4-hydroxyphenyl) propane, 1,1-bis(4-hydroxyphenyl) n-butane,2,2-bis(4-hydroxy-1-methylphenyl) propane, and1,1-bis(4-hydroxy-t-butylphenyl) propane; resorcinol, substitutedresorcinol compounds such as 5-methyl resorcinol, 5-phenyl resorcinol,or 5-cumyl resorcinol; catechol; hydroquinone; and substitutedhydroquinones such as 2-methyl hydroquinone, 2-t-butyl hydroquinone,2-phenyl hydroquinone, 2-cumyl hydroquinone, or 2,3,5,6-tetramethylhydroquinone. Bisphenol-A is often part of the PC—Si copolymer.

The polymer resin (polymer B) in the blend can be a polycarbonate resinhaving an aliphatic chain containing at least two carbon atoms as arepeating unit in the polymer backbone. This resin can also beconsidered a “soft segment polycarbonate” (SSP) resin. Generallyspeaking, the SSP resin is a copolymer of an aromatic difunctionalcompound and an aliphatic difunctional compound. The aromaticdifunctional compound may have the structure of, for example, any ofFormulas (A)-(H), previously described as chain extenders above. Inspecific embodiments, the aromatic difunctional compound is a bisphenolof Formula (A). The aliphatic difunctional compound provides a longaliphatic chain in the backbone and may have the structure of Formula(D). Exemplary aliphatic diols that are useful in SSP resins includeadipic acid (n=4), sebacic acid (n=8), and dodecanedioic acid (n=10).The SSP resin can be formed, for example by the phosgenation ofbisphenol-A, sebacic acid, and p-cumyl phenol. The SSP resin containscarbonate linkages and ester linkages.

In this regard, it is believed that the cross-linking reaction rate ofthe cross-linkable polycarbonate resin and its yield are directlyrelated to the hydrogen-to-ketone ratio of the polymeric blend. Thus,the higher the hydrogen-to-ketone ratio of the blend, the higher therate of chain-extension reaction/crosslinking should be. Due to thepresence of the hydrogen-rich SSP resin with its aliphatic blocks, thehydrogen-to-ketone ratio is relatively high. As a result, thecrosslinking density and the resulting flame retardance and chemicalresistance should be very good for this blend. In addition, the SSPresin has very good flow properties. It is believed that the blendshould also have good flow, and should also retain its ductileproperties even after crosslinking.

The polymer resin (polymer B) in the blend can be a bisphenol-Ahomopolycarbonate. Such resins are available, for example as LEXAN™ fromSABIC Innovative Plastics.

The polymer resin (polymer B) in the blend can be a polystyrene polymer.Such polymers contain only polystyrene monomers. Thus, for example ABSand MBS should not be considered polystyrene polymers.

The polymer resin (polymer B) in the blend can be a thermoplasticpolyester. An exemplary polyester is PCTG, which is a copolymer derivedfrom the reaction of terephthalic acid, ethylene glycol, andcyclohexanedimethanol (CHDM). The PCTG copolymer can contain 40-90 mole% CHDM, with the terephthalic acid and the ethylene glycol making up theremaining 10-60 mole %.

The polymer resin (polymer B) in the blend can be a dimethyl bisphenolcyclohexane-co-bisphenol-A copolymer, i.e. a DMBPC-BPA copolymer. TheDMBPC is usually from 20 mole % to 90 mole % of the copolymer, including25 mole % to 60 mole %. The BPA is usually from 10 mole % to 80 mole %of the copolymer, including 40 mole % to 75 mole %. These resins havehigh scratch resistance.

Other Additives

Other conventional additives can also be added to the polymericcomposition (e.g. an impact modifier, UV stabilizer, colorant, flameretardant, heat stabilizer, plasticizer, lubricant, mold release agent,filler, reinforcing agent, antioxidant agent, antistatic agent, blowingagent, or radiation stabilizer).

In preferred embodiments, the blend compositions disclosed hereincomprise a flame-retardant, a flame retardant additive, and/or an impactmodifier. The flame-retardant may be potassium perfluorobutane sulfonate(Rimar salt), potassium diphenyl sulfone-3-sulfonate (KSS), or acombination thereof.

Various types of flame retardants can be utilized as additives. Thisincludes flame retardant salts such as alkali metal salts ofperfluorinated C₁-C₁₆ alkyl sulfonates such as potassium perfluorobutanesulfonate (Rimar salt), potassium perfluoroctane sulfonate,tetraethylammonium perfluorohexane sulfonate, potassium diphenylsulfonesulfonate (KSS), and the like, sodium benzene sulfonate, sodium toluenesulfonate (NATS) and the like. Rimar salt and KSS and NATS, alone or incombination with other flame retardants, are particularly useful in thecompositions disclosed herein. In certain embodiments, the flameretardant does not contain bromine or chlorine, i.e. is non-halogenated.Another useful class of flame retardant is the class of cyclic siloxaneshaving the general formula [(R)₂SiO]_(y) wherein R is a monovalenthydrocarbon or fluorinated hydrocarbon having from 1 to 18 carbon atomsand y is a number from 3 to 12. A particularly useful cyclic siloxane isoctaphenylcyclotetrasiloxane.

Exemplary heat stabilizer additives include, for example,organophosphites such as triphenyl phosphite,tris-(2,6-dimethylphenyl)phosphite, tris-(mixed mono- anddi-nonylphenyl)phosphite or the like; phosphonates such asdimethylbenzene phosphonate or the like; phosphates such as trimethylphosphate, or the like; or combinations comprising at least one of theforegoing heat stabilizers. Heat stabilizers are generally used inamounts of 0.0001 to 1 part by weight, based on 100 parts by weight ofthe polymer component of the polymeric blend/composition.

Mold release agent (MRA) will allow the material to be removed quicklyand effectively. Mold releases can reduce cycle times, defects, andbrowning of finished product. Exemplary MRAs include phthalic acidesters; di- or polyfunctional aromatic phosphates such as resorcinoltetraphenyl diphosphate (RDP), the bis(diphenyl) phosphate ofhydroquinone and the bis(diphenyl) phosphate of bisphenol-A;pentaerythritol tetrastearate (PETS), and the like. Such materials aregenerally used in amounts of 0.001 to 1 part by weight, specifically0.01 to 0.75 part by weight, more specifically 0.1 to 0.5 part byweight, based on 100 parts by weight of the polymer component of thepolymeric blend/composition.

In particular embodiments, the polymeric blend/composition includes thecross-linkable polycarbonate resin, an optional polymeric base resin,and a flame retardant which is Rimar salt and which is present in anamount of about 0.05 wt % to about 0.085 wt %, based on the total weightof the composition; and a plaque comprising the polymeric compositionhas a transparency of 70 to 90% at a thickness of 3.2 mm, measuredaccording to ASTM D1003-13.

In other particular embodiments, the polymeric blend/compositionincludes the cross-linkable polycarbonate resin, an optional polymericbase resin, a flame retardant; a heat stabilizer, and a mold releaseagent.

The additives, when used, can improve various properties of the finalarticle. Increased chemical resistance may be found against 409 Glassand Surface Cleaner; Alcohol Prep Pad; CaviCide liquid/CaviWipes;CaviWipes; Cidex Plus liquid; Clorox Bleach; Clorox Wipes; Envirocideliquid; ForPro liquid; Gentle dish soap and water; Hydrogen PeroxideCleaner Disinfectant Wipes; Isopropyl Alcohol wipes; MadaCide-1 liquid;Mar-V-Cide liquid to dilute; Sani-Cloth Bleach Wipes; Sani-Cloth HBWipes; Sani-Cloth Plus Wipes; Sodium Hypochlorite liquid; SuperSani-Cloth Wipes; Viraguard liquid and Wipes; Virex 256; Windex Blue;Fuel C; Toluene; Heptane; Ethanol; Isopropanol; Windex; Engine oil;WD40; Transmission fluid; Break fluid; Glass wash; Diesel; Gasoline;Banana Boat Sunscreen (SPF 30); Sebum; Ivory Dish Soap; SC JohnsonFantastik Cleaner; French's Yellow Mustard; Coca-Cola; 70% IsopropylAlcohol; Extra Virgin Olive Oil; Vaseline Intensive Care Hand Lotion;Heinz Ketchup; Kraft Mayonnaise; Chlorox Formula 409 Cleaner; SC JohnsonWindex Cleaner with Ammonia; Acetone; Artificial Sweat; Fruits & PassionCucina Coriander & Olive Hand Cream; Loreal Studioline Megagel Hair Gel;Maybelline Lip Polish; Maybelline Expert Wear Blush—Beach Plum Rouge;Purell Hand Sanitizer; Hot coffee, black; iKlear; Chlorox Wipes;Squalene; Palmitic Acid; Oleic Acid; Palmitoleic Acid; Stearic Acid; andOlive Oil.

Articles

The compositions/blends can be molded into useful shaped articles by avariety of means such as injection molding, overmolding, co-injectionmolding, extrusion, multilayer extrusion, rotational molding, blowmolding and thermoforming to form articles. This includes thin-walledarticles, including highly transparent thin-walled articles. The formedarticles may be subsequently subjected to cross-linking conditions(e.g., UV-radiation) to affect cross-linking of the polycarbonates.Exemplary articles include a film, a sheet, a layer of a multilayerfilm, or a layer of a multilayer sheet.

Articles that may be formed from the compositions/blends include variouscomponents for cell phones and cell phone covers, components forcomputer housings (e.g. mouse covers), fibers, computer housings andbusiness machine housings and parts such as housings and parts formonitors, computer routers, copiers, desk top printers, largeoffice/industrial printers handheld electronic device housings such ascomputer or business machine housings, housings for hand-held devices,components for light fixtures or home or office appliances, humidifierhousings, thermostat control housings air conditioner drain pans,outdoor cabinets, telecom enclosures and infrastructure, Simple NetworkIntrusion Detection System (SNIDS) devices, network interface devices,smoke detectors, components and devices in plenum spaces, components formedical applications or devices such as medical scanners, X-rayequipment, and ultrasound devices, components for interior or exteriorcomponents of an automobile, lenses (auto and non-auto) such ascomponents for film applications, greenhouse components, sun roomcomponents, fire helmets, safety shields, safety goggles, glasses withimpact resistance, fendors, gas pumps, films for televisions, such asecofriendly films having no halogen content, solar applicationmaterials, glass lamination materials, fibers for glass-filled systems,hand held electronic device enclosures or parts (e.g. walkie-talkie,scanner, media/MP3/MP4 player, radio, GPS system, ebook, tablet),wearable electronic devices (e.g. smart watch, training/tracking device,activity/sleep monitoring system, wristband, or glasses), hand held toolenclosures or parts, smart phone enclosures or parts, turbine blades(e.g., wind turbines), and the like.

In certain embodiments, articles that may comprise the composition/blendinclude automotive bumpers, other automotive, construction andagricultural equipment exterior components, automobile mirror housings,an automobile grille, an automobile pillar, automobile wheel covers,automobile, construction and agricultural equipment instrument panelsand trim, construction and agricultural grilles, automobile glove boxes,automobile door hardware and other interior trim, automobileconstruction and agricultural equipment exterior lights, automobileparts within the engine compartment, plumbing equipment, valves andpumps, air conditioning heating and cooling parts, furnace and heat pumpparts, computer parts, electronics parts, projector parts, electronicdisplay parts, copier parts, scanner parts, electronic printer tonercartridges, hair driers, irons, coffee makers, toasters, washingmachines, microwaves, ovens, power tools, electric components, lightingparts, dental instruments and equipment, medical instruments, cookware,medical instrument trays, animal cages, fibers, laser welded medicaldevices, hand held electronic device enclosures or parts (e.g.walkie-talkie, scanner, media/MP3/MP4 player, radio, GPS system, ebook,tablet), wearable electronic devices (e.g. smart watch,training/tracking device, activity/sleep monitoring system, wristband,or glasses), hand held tool enclosures or parts, smart phone enclosuresor parts, and fiber optics.

In certain embodiments, articles that may comprise the composition/blendinclude automotive bumpers, other automotive exterior components,automobile mirror housings, an automobile grille, an automobile pillar,automobile wheel covers, automobile instrument panels and trim,automobile glove boxes, automobile door hardware and other interiortrim, external automobile trim parts, such as pillars, automobileexterior lights, automobile parts within the engine compartment, anagricultural tractor or device part, a construction equipment vehicle ordevice part, a construction or agricultural equipment grille, a marineor personal water craft part, an all-terrain vehicle or all-terrainvehicle part, plumbing equipment, valves and pumps, air conditioningheating and cooling parts, furnace and heat pump parts, computer parts,electronics parts, projector parts, electronic display parts, copierparts, scanner parts, electronic printer toner cartridges, hair driers,irons, coffee makers, toasters, washing machines, microwaves, ovens,power tools, electric components, electric enclosures, lighting parts,dental instruments, medical instruments, medical or dental lightingparts, an aircraft part, a train or rail part, a seating component,sidewalls, ceiling parts, cookware, medical instrument trays, animalcages, fibers, laser welded medical devices, fiber optics, lenses (autoand non-auto), cell phone parts, greenhouse components, sun roomcomponents, fire helmets, safety shields, safety glasses, gas pumpparts, hand held electronic device enclosures or parts (e.g.walkie-talkie, scanner, media/MP3/MP4 player, radio, GPS system, ebook,tablet), wearable electronic devices (e.g. smart watch,training/tracking device, activity/sleep monitoring system, wristband,or glasses), hand held tool enclosures or parts, smart phone enclosuresor parts, and turbine blades.

In certain embodiments, the article is one that requires or must includea material having a UL94 5VA rating performance. Articles that require aUL94 5VA rating include, but are not limited to, computer housings,computer housings and business machine housings and parts such ashousings and parts for monitors, computer routers, copiers, desk topprinters, large office/industrial printers, handheld electronic devicehousings such as computer or business machine housings, housings forhand-held devices, components for light fixtures including LED fixturesor home or office appliances, humidifier housings, thermostat controlhousings, air conditioner drain pans, outdoor cabinets, telecomenclosures and infrastructure, Simple Network Intrusion Detection System(SNIDS) devices, network interface devices, smoke detectors, componentsand devices in plenum spaces, components for medical applications ordevices such as medical scanners, X-ray equipment, and ultrasounddevices, electrical boxes and enclosures, and electrical connectors.

In certain embodiments, the article is one that requires hydrothermalstability, such as a wind turbine blade, a steam sterilizable medicaldevice, a food service tray, utensils and equipment.

In certain embodiments, the article is one that requires a combinationof transparency, flame resistance, and/or impact resistance. Forexample, in certain embodiments the article may be a safety shield,safety goggles, a gas/fuel pump housing, a display window or part, orthe like.

Ultraviolet Irradiation

After forming the article, the article can then be exposed toultraviolet (UV) light at an appropriate wavelength and dosage to bringabout the desired amount of crosslinking for the given application. TheUV exposure can be performed on one or more surfaces of the article.

The article should be exposed with a substantially uniform dose of UVlight. The exposure can be accomplished using standard methods. The UVlight can come from any source of UV light such as mercury vapor,High-Intensity Discharge (HID), or various UV lamps. The exposure timecan range from a few minutes to several days. Examples of UV-emittinglight bulbs include mercury bulbs (H bulbs), or metal halide dopedmercury bulbs (D bulbs, H+ bulbs, and V bulbs). Other combinations ofmetal halides to create a UV light source are also contemplated. Amercury arc lamp is not used for irradiation. An H bulb has strongoutput in the range of 200 nm to 320 nm. The D bulb has strong output inthe 320 nm to 400 nm range. The V bulb has strong output in the 400 nmto 420 nm range. It may also be advantageous to use a UV light sourcewhere the harmful wavelengths are removed or not present, using filters.

It may also be advantageous to use a UV light source where the harmfulwavelengths (those that cause polymer degradation or excessiveyellowing) are removed or not present. Equipment suppliers such asHeraeus Noblelight and Fusion UV provide lamps with various spectraldistributions. The light can also be filtered to remove harmful orunwanted wavelengths of light. This can be done with optical filtersthat are used to selectively transmit or reject a wavelength or range ofwavelengths. These filters are commercially available from a variety ofcompanies such as Edmund Optics or Praezisions Glas & Optik GmbH.Bandpass filters are designed to transmit a portion of the spectrum,while rejecting all other wavelengths. Longpass edge filters aredesigned to transmit wavelengths greater than the cut-on wavelength ofthe filter. Shortpass edge filters are used to transmit wavelengthsshorter than the cut-off wavelength of the filter. Various types ofmaterials, such as borosilicate glass, can be used as a long passfilter. Schott and/or Praezisions Glas & Optik GmbH for example have thefollowing long pass filters: WG225, WG280, WG295, WG305, WG320 whichhave cut-on wavelengths of ˜225, 280, 295, 305, and 320 nm,respectively. These filters can be used to screen out the harmful shortwavelengths while transmitting the appropriate wavelengths for thecrosslinking reaction.

In particular embodiments, the polycarbonates are exposed to a selectedUV light range having wavelengths from about 280 nanometers (nm) toabout 380 nm, or from about 330 nm to about 380 nm, or from about 280 nmto about 360 nm, or from about 330 nm to about 360 nm. The wavelengthsin a “selected” light range have an internal transmittance of greaterthan 50%, with wavelengths outside of the range having an internaltransmittance of less than 50%. The change in transmittance may occurover a range of 20 nm. Reference to a selected light range should not beconstrued as saying that all wavelengths within the range transmit at100%, or that all wavelengths outside the range transmit at 0%.

In some embodiments, the UV radiation is filtered to provide exposure toUVA radiation with no detectable UVC radiation, as measured using an EITPowerPuck. The effective dosage can range from at least 2 Joules persquare centimeter (J/cm²) of UVA radiation up to about 60 J/cm² of UVAradiation. In more specific embodiments, the UV radiation is filtered toprovide an effective dosage of at least 3 J/cm², or at least 12 J/cm²,or at least 21 J/cm², or at least 36 J/cm² of UVA radiation, with nodetectable UVC radiation, as measured using an EIT PowerPuck. Inparticular embodiments, the polycarbonates are exposed to a dosage ofabout 21 J/cm² to about 60 J/cm² of UVA radiation, or in more particularembodiments a dosage of about 21 J/cm² to about 36 J/cm² of UVAradiation.

The exposed article will have a cross-linked outer surface and an innersurface that is either lightly cross-linked or not cross-linked. Theouter surface can be cross-linked to such a degree that the outersurface is substantially insoluble in the common solvents for thestarting resins. The percentage of the insolubles (insoluble component)will be dependent on the part geometry and surface-to-volume ratio.

Predictive Equations

The photoactive additives of the present disclosure are intended to beused to improve the properties of articles in which they areincorporated. Those properties include (1) the ability of the article topass the UL94 V0 flame retardance test; (2) maintain a high percentretention of tensile elongation; (3) have a low delta YI; (4) have a lowdelta % T; and (5) have a high gel thickness. These properties can beaffected by the makeup of the cross-linkable polycarbonate resin, theamount of the cross-linkable polycarbonate resin used to form thearticle, and the dosage of UV radiation needed to induce crosslinking.

Relevant properties of the polycarbonate resin can include the contentof the dihydroxybenzophenone, expressed in molar percentage; and themelt flow rate of the polycarbonate resin, which is inverselyproportional to the molecular weight of the resin, expressed in g/10min. Relevant properties of the blend can include the weight percentageof the cross-linkable polycarbonate resin.

Five polynomial equations have been determined that provide a model fitfor each desired property of the article. The parameters in theequations include (1) the UV dosage, D, in J/cm² for UVA radiation; (2)the dihydroxybenzophenone level in the crosslinkable polycarbonate, inmole %, MOL %; (3) the molecular weight increase in the polymericcomposition after exposure to the UV radiation, MW_I, in Daltons; (4)the melt flow rate of the polycarbonate blend, MF, in g/10 min; and (5)the weight percentage of the cross-linkable polycarbonate resin in theblend, WP. The five model equations are shown below. In these equations,“Ln” refers to the natural log (base e), and “sqrt” indicates the squareroot.

Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL%)²)−(0.017115×(MF)²)  Eqn 1:

Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL%)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)  Eqn 2:

Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I)  Eqn 3:

(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF)  Eqn 4:

Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²)  Eqn 5:

Equation 1 predicts the flame performance of the article. In thisregard, flammability testing can be conducted using the standardUnderwriters Laboratory UL 94 test method (2 day or 7 day conditioning)described in the Underwriter's Laboratory Bulletin 94 entitled “Testsfor Flammability of Plastic Materials, UL94”. In this test method,specimens are preconditioned in two ways: (a) either at room temperaturefor 48 hours or (b) in an air-circulating oven for 168 hours at 70±1° C.and then cooled in a desiccator for at least 4 hours at roomtemperature, prior to testing. Once removed from the desiccator,specimens are tested within 30 minutes.

Several ratings can be applied based on the rate of burning, time toextinguish, ability to resist dripping, and whether or not drips areburning. According to UL94, materials may be classified as HB, V0, V1,V2, 5V, 5VA and/or 5VB on the basis of the test results obtained forfive samples. The criteria for the flammability classifications or“flame retardance” are described below.

V0: A specimen is supported in a vertical position and a flame isapplied to the bottom of the specimen. The flame is applied for tenseconds and then removed until flaming stops at which time the flame isreapplied for another ten seconds and then removed. Two sets of fivespecimens are tested. The two sets are conditioned under differentconditions.

To achieve a V0 rating, specimens must not burn with flaming combustionfor more than 10 seconds after either test flame application. Totalflaming combustion time must not exceed 50 seconds for each set of 5specimens. Specimens must not burn with flaming or glowing combustion upto the specimen holding clamp. Specimens must not drip flaming particlesthat ignite the cotton. No specimen can have glowing combustion remainfor longer than 30 seconds after removal of the test flame

5VA: Testing is done on both bar and plaque specimens. Procedure forBars: A bar specimen is supported in a vertical position and a flame isapplied to one of the lower corners of the specimen at a 20° angle. Theflame is applied for 5 seconds and is removed for 5 seconds. The flameapplication and removal is repeated five times. Procedure for Plaques:The procedure for plaques is the same as for bars except that the plaquespecimen is mounted horizontally and a flame is applied to the center ofthe lower surface of the plaque.

To achieve a 5VA rating, specimens must not have any flaming or glowingcombustion for more than 60 seconds after the five flame applications.Specimens must not drip flaming particles that ignite the cotton. Plaquespecimens must not exhibit burnthrough (a hole). It is noted that in theExamples and Tables below, the rows that state whether 5VA was “Pass” or“Fail” for a given thickness refer only to whether the plaque test waspassed, and should not be interpreted as stating that no combustionoccurred for more than 60 seconds and that there were no drips. Resultsfor both 2-day and 7-day conditioning are reported.

The data can be analyzed by calculation of the average flame out time,standard deviation of the flame out time and the total number of drips.Statistical methods can then be used to convert the data to aprobability that a specific formulation will achieve a first time V0pass or “p(FTP)” in the standard UL 94 testing of 5 bars. Theprobability of a first time pass on a first submission (pFTP) may bedetermined according to the formula:

pFTP=(P_(t1>mbt, n=0)×P_(t2>mbt, n=0)×P_(total<=mtbt)×P_(drip, n=0))

where P_(t1>mbt, n=0) is the probability that no first burn time exceedsa maximum burn time value, P_(t2>mbt, n=0) is the probability that nosecond burn time exceeds a maximum burn time value, P_(total<=mtbt) isthe probability that the sum of the burn times is less than or equal toa maximum total burn time value, and P_(drip, n=0) is the probabilitythat no specimen exhibits dripping during the flame test. First andsecond burn time refer to burn times after a first and secondapplication of the flame, respectively.

The probability that no first burn time exceeds a maximum burn timevalue, P t1>mbt, n=0, may be determined from the formula:P_(t1>mbt, n=0)=(1−P_(t1>mbt))⁵ where P_(t1>mbt) is the area under thelog normal distribution curve for t1>mbt, and where the exponent “5”relates to the number of bars tested. The probability that no secondburn time exceeds a maximum burn time value may be determined from theformula: P_(t2>mbt, n=0)=(1−P_(t2>mbt)) where P_(t2>mbt) is the areaunder the normal distribution curve for t2>mbt. As above, the mean andstandard deviation of the burn time data set are used to calculate thenormal distribution curve. For the UL-94 V-0 rating, the maximum burntime is 10 seconds. For a V-1 or V-2 rating the maximum burn time is 30seconds. The probability P_(drip, n=0) that no specimen exhibitsdripping during the flame test is an attribute function, estimated by:(1−P_(drip))⁵ where P_(drip)=(the number of bars that drip/the number ofbars tested).

The probability P_(total<=mtbt) that the sum of the burn times is lessthan or equal to a maximum total burn time value may be determined froma normal distribution curve of simulated 5-bar total burn times. Thedistribution may be generated from a Monte Carlo simulation of 1000 setsof five bars using the distribution for the burn time data determinedabove. Techniques for Monte Carlo simulation are well known in the art.A normal distribution curve for 5-bar total burn times may be generatedusing the mean and standard deviation of the simulated 1000 sets.Therefore, P_(total<=mtbt) may be determined from the area under a lognormal distribution curve of a set of 1000 Monte Carlo simulated 5-bartotal burn time for total<=maximum total burn time. For the UL94 V0rating, the maximum total burn time is 50 seconds.

pFTP values range from zero (i.e. absolute probability of failing theUL94 test) to 1.0 (i.e. absolute probability of passing the UL94 test).Preferably, pFTP values will be 1 or very close to 1 for high confidencethat a sample formulation will achieve a V0 rating in UL 94 testing.

A pFTP value can be obtained for flammability tests conducted after 2days conditioning and after 7 days conditioning. In Equation 1, thevalue of V0_Avg is the average of the pFTP values for the two-day testand the seven-day test. V0_Avg will have a value between 0.0 and 1.0.

In Equation 2, % RE is the percentage retention of tensile elongationafter exposure to acetone at a thickness of 3.2 mm. % RE is expressed inpercentages. For example, if the percentage retention is 105%, % RE willbe 105, not 1.05.

In Equation 3, D_YI is the change in Yellowness Index, measured beforeUVA exposure and at least 48 hours after the UVA exposure. D_YI isexpressed in dimensionless YI units.

In Equation 4, D_% T is the change in light transmission, measuredbefore UVA exposure and at least 48 hours after UVA exposure. D_% T isexpressed in percentages. For example, if the change is 3%, D_% T willbe 3, not 0.03.

In Equation 5, GEL is the gel thickness on a surface of the article,measured in micrometers.

The dihydroxybenzophenone level in the crosslinkable polycarbonate, MOL%, is expressed in percentages. For example, if the polycarbonatecontains 3 mole %, then MOL % will be 3, not 0.03.

Similarly, the weight percentage of the cross-linkable polycarbonateresin in the blend, WP, is also measured in percentages. For example, ifthe blend contains 20 wt % of polycarbonate resin, then WP will be 20,not 0.20.

These equations can be used alone or combined to design articles havingdesired combinations of properties and to predict the resultingproperties of the article depending on the makeup of the cross-linkablepolycarbonate resin and the polycarbonate blend. Typically, a highV0_Avg, a high % RE, a low D_YI, a low D_% T, and a high GEL aredesired. Desirably, V0_Avg is at least 0.7; % RE is at least 85; and/orD_YI is less than 6.

The characteristics for model Equations 1-3 are shown below:

Average V0 p(FTP) Elongation Retention Delta Yl Adjusted R-Squared0.8657 0.9060 0.9138 Predicted R-Squared 0.7377 0.8529 0.8983 AdequatePrecision 13.805 16.503 25.256

The predicted R-Squareds all show reasonable agreement with the AdjustedR-Sqared values. Adequate Precision measures the signal to noise ratio.A ratio greater than 4 is generally desirable. Here, the ratios rangefrom 13.8 to 25.3, which indicates an adequate signal and thus thesemodels can be used to navigate the design space.

The following examples are provided to illustrate the polymericcompositions/blends, articles, processes, and properties of the presentdisclosure. The examples are merely illustrative and are not intended tolimit the disclosure to the materials, conditions, or process parametersset forth therein.

EXAMPLES

A large scale study was performed using 16 different batches. Thebatches were made using the ingredients listed in Table A. Thecross-linkable resins were copolymers made from4,4′-dihydroxybenzophenone (DHBP) and bisphenol-A (BPA).

TABLE A Com- Mw ponent Description Daltons XPC-A Copolymer with 2.5 mole% DHBP, remainder BPA ~23,000 XPC-B Copolymer with 2.5 mole % DHBP,remainder BPA ~27,500 XPC-C Copolymer with 2.5 mole % DHBP, remainderBPA ~32,000 XPC-D Copolymer with 11 mole % DHBP, remainder BPA ~23,000XPC-E Copolymer with 11 mole % DHBP, remainder BPA ~27,500 XPC-FCopolymer with 11 mole % DHBP, remainder BPA ~32,000 XPC-G Copolymerwith 20 mole % DHBP, remainder BPA ~23,000 XPC-H Copolymer with 20 mole% DHBP, remainder BPA ~27,500 XPC-J Copolymer with 20 mole % DHBP,remainder BPA ~32,000 LF-PC Low-flow bisphenol-A homopolymer ~31,000Rimar Salt Potassium perfluorobutanesulfonate CyclicOctaphenylcyclotetrasiloxane siloxane Phosphite Tris(2,4-di-tert-butylphenyl) phosphite Stabilizer

The formulation of the 16 different batches is shown in Table 1A andTable 1B. The units are phr.

TABLE 1A Ingredient B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8 B-9 XPC-A 100 50XPC-B 75 50 XPC-C 100 50 XPC-D 100 50 XPC-E 75 LF-PC 50 25 50 50 50 25Rimar Salt 0.080 0.080 0.080 0.080 0.080 0.080 0.080 0.080 0.080 CyclicSiloxane 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 0.100 Phosphite0.060 0.060 0.060 0.060 0.060 0.060 0.060 0.060 0.060 stabilizer

TABLE 1B Ingredient B-10 B-11 B-12 B-13 B-14 B-15 B-16 XPC-F 50 XPC-G100 75 50 XPC-H 50 XPC-J 100 50 LF-PC 50 25 50 50 50 Rimar Salt 0.0800.080 0.080 0.080 0.080 0.080 0.080 Cyclic Siloxane 0.100 0.100 0.1000.100 0.100 0.100 0.100 Phosphite stabilizer 0.060 0.060 0.060 0.0600.060 0.060 0.060

Various properties of the 16 batches were measured.

The MFR was calculated using the ASTM D1238-13 method, 1.2 kg load, 300°C. temperature, 360 second or 1080 second dwell.

Molecular weight determinations were performed using gel permeationchromatography (GPC), using a cross-linked styrene-divinylbenzene columnand calibrated to polycarbonate references using a UV-VIS detector setat 264 nm. Samples were prepared at a concentration of about 1 mg/ml,and eluted at a flow rate of about 1.0 ml/min.

The molar percentage of DHBP was measured by liquid chromatography.

The Yellowness Index was measured before and/or after UV exposure usingan X-Rite Color i7 benchtop spectrophotometer in the transmission modeusing CIELAB color equation, an observer angle of 2 degrees, andilluminant C as the light source. YI was measured following ASTM E313-73(D1925). The light transmission (% T) was measured concurrently with theYI on the same bar.

The properties are listed in Table 2.

TABLE 2 MFR MFR DHBP (360 sec) (1080 sec) Mw PDI (%) % T YI B-1 19.820.3 22069 2.3 2.63 88.34 3.32 B-2 11.3 11.3 25607 2.6 1.3 89.04 2.06B-3 9.12 9.5 27093 2.6 1.96 88.30 2.93 B-4 8.52 8.71 27548 2.4 1.3288.88 2.33 B-5 5.55 5.81 30697 2.5 2.65 88.06 3.69 B-6 6.07 6.71 298322.4 1.33 88.95 2.28 B-7 16.2 17 24997 2.6 10.83 87.62 4.77 B-8 10.8 11.426213 2.2 5.32 88.41 3.07 B-9 9.23 9.62 25393 2.3 8.68 87.83 4.71 B-106.63 6.96 30130 2.4 5.84 87.57 5.20 B-11 17.6 18.6 23456 2.3 20.25 87.176.52 B-12 13.6 14.9 24993 2.3 15.18 87.86 5.11 B-13 11.3 12.7 26343 2.210.22 88.34 4.25 B-14 8.65 9.49 28204 2.3 10.84 87.78 5.36 B-15 6.045.97 31062 2.2 21.39 86.32 8.48 B-16 6.38 6.93 30574 2.4 10.87 87.975.24

The 16 batches were used to make 40 samples which were exposed to UVlight. Samples were exposed to filtered UV light provided by a LoctiteZeta 7411-S system, which used a 400 W metal halide arc lamp and behavedlike a D-bulb electrodeless bulb in spectral output with a 280-nm cut-onwavelength filter. This was done because in prior experiments, filteredlight showed a lower change in YI for equivalent doses of UVA comparedto unfiltered UV light. The samples were exposed on both sides beneaththe UV lights for the equivalent UVA dosage of 6, 21, or 36 J/cm² perside. The UV energy for the Loctite system is provided below in Table B,and was measured using an EIT UV PowerPuck® II. The dose was measured asthe energy from 320-390 nm (UVA), 280-320 nm (UVB), 250-260 nm (UVC) and395-445 nm (UVV). The dose was calculated in J/cm².

TABLE B Loctite (filtered light). Loctite Dose UVA UVB UVC UVV FilteredJ/cm² J/cm² J/cm² J/cm² 160 sec exposure 6.0 1.2 0 3.7 560 sec exposure21.0 4.2 0 12.8 960 sec exposure 36.0 7.2 0 21.9

The flame performance of the 40 samples was tested using the methodsdescribed above. The pFTP values for these samples were based on 20 barsof 1.2 mm thickness. The bars were conditioned for either 2 days or 7days, then tested. The pFTP was calculated separately for the 2-daysamples and the 7-day samples. The pFTP for V0 performance and V1performance was calculated. It should be noted that the pFTP(V1) for anygiven sample is expected to be higher than the pFTP(V0) for the sample,because the V1 test is less stringent than the V0 test.

Chemical resistance was measured by the elongation at break of tensilebars having 3.2 mm thickness. For chemically exposed samples, thetensile bars were put under 1% strain at 23° C. and exposed to acetone.They were then removed from the strain jigs and the tensile elongationat break was measured following the ASTM D638-10 Type I method at 50mm/min. The tensile elongation at break was measured under fourdifferent conditions: before UV exposure and before exposure to acetone(“No UV, No Chem”); before UV exposure and after exposure to acetone(“No UV, Ace”); after UV exposure and before exposure to acetone (“UV,No Chem”); and after UV exposure and after exposure to acetone (“UV,Ace”). Units were in percentage. The percentage of retention of tensileelongation (% RE) was the “UV, Ace” divided by the “UV, No Chem”.Acetone was applied to six bars, while the “No Chem” control data wasobtained with only 3 bars.

The degree of crosslinking was quantified by dissolving thenon-cross-linked fraction of the plaque in methylene chloride andisolating the insoluble gel layer. The thickness of the insoluble gellayer was measured using optical microscopy, and is reported inmicrometers.

The molecular weight, Yellowness Index (YI), and light transmission (%T) were measured as described above. The MFR for each sample wascalculated using the ASTM D1238-13 method, 1.2 kilogram (kg) load, 300°C. temperature, 360 second dwell.

The results of the 40 samples are reported in Tables 3A-3F.

TABLE 3A Dosage Gel Molecular Weight Run Batch # J/cm² (micron) BeforeUV After UV Delta 1 B-15 36 52.3 31062 35160 4098 2 B-6 21 0.0 2983237953 8121 3 B-13 6 5.7 26343 28381 2038 4 B-9 36 64.6 25393 32938 75455 B-13 6 3.7 26343 27752 1409 6 B-15 6 7.6 31062 32393 1331 7 B-5 36 8.130697 40781 10084 8 B-15 6 6.8 31062 31723 661 9 B-1 36 7.3 22069 291857116 10 B-16 36 45.4 30574 36286 5712 11 B-15 36 40.5 31062 35070 400812 B-14 6 5.0 28204 30330 2126 13 B-5 6 0.0 30697 33519 2822 14 B-9 2148.4 25393 31243 5850 15 B-16 6 5.7 30574 32966 2392 16 B-4 6 0.0 2754830164 2616 17 B-5 6 0.0 30697 33796 3099 19 B-9 21 24.2 25393 31409 601620 B-14 21 47.6 28204 31647 3443 21 B-11 6 5.1 23456 25514 2058 22 B-1136 49.2 23456 26395 2939 23 B-7 6 2.8 24997 25626 629 24 B-11 36 62.023456 26850 3394 25 B-11 6 4.3 23456 24946 1490 26 B-16 36 64.0 3057435423 4849 27 B-15 36 55.5 31062 34265 3203 28 B-10 6 3.7 30130 327462616 29 B-12 36 49.3 24993 27661 2668 30 B-5 36 25.1 30697 40239 9542 31B-1 21 5.7 22069 28264 6195 32 B-2 6 0.0 25607 27710 2103 33 B-13 2121.9 26343 30145 3802 34 B-15 21 38.4 31062 34101 3039 35 B-12 6 6.224993 26783 1790 36 B-14 6 3.5 28204 30986 2782 37 B-8 36 50.6 2621331459 5246 39 B-6 36 0.0 29832 40473 10641 40 B-2 36 0.0 25607 346028995 41 B-3 21 1.9 27093 35118 8025

TABLE 3B 1.2 mm flame Dosage p (FTP) @ V0 Run Batch # J/cm2 2 day 7 dayAvg 1 B-15 36 0.3946 0.7785 0.5866 2 B-6 21 0.9373 0.0838 0.5106 3 B-136 0.0234 0.0080 0.0157 4 B-9 36 0.3691 0.6592 0.5142 5 B-13 6 0.09700.0160 0.0565 6 B-15 6 0.0005 0.0000 0.0003 7 B-5 36 0.9769 0.93870.9578 8 B-15 6 0.0076 0.0000 0.0038 9 B-1 36 0.2127 0.3261 0.2694 10B-16 36 0.6280 0.4036 0.5158 11 B-15 36 0.4196 0.7577 0.5887 12 B-14 60.1887 0.0428 0.1158 13 B-5 6 0.9732 0.2302 0.6017 14 B-9 21 0.00150.3255 0.1635 15 B-16 6 0.0127 0.0509 0.0318 16 B-4 6 0.6589 0.01110.3350 17 B-5 6 0.7649 0.1791 0.4720 19 B-9 21 0.5059 0.5040 0.5050 20B-14 21 0.3871 0.8785 0.6328 21 B-11 6 0.0000 0.0000 0.0000 22 B-11 360.0211 0.1796 0.1004 23 B-7 6 0.0000 0.0009 0.0005 24 B-11 36 0.00000.2521 0.1261 25 B-11 6 0.0263 0.0000 0.0132 26 B-16 36 0.4977 0.65800.5779 27 B-15 36 0.9810 0.6463 0.8137 28 B-10 6 0.0673 0.1563 0.1118 29B-12 36 0.7543 0.8705 0.8124 30 B-5 36 0.9555 0.9983 0.9769 31 B-1 210.0093 0.0001 0.0047 32 B-2 6 0.0041 0.0000 0.0021 33 B-13 21 0.00000.1287 0.0644 34 B-15 21 0.1210 0.2359 0.1785 35 B-12 6 0.0486 0.15230.1005 36 B-14 6 0.4216 0.0265 0.2241 37 B-8 36 0.4735 0.3092 0.3914 39B-6 36 0.9085 0.2432 0.5759 40 B-2 36 0.7347 0.4193 0.5770 41 B-3 210.9521 0.4232 0.6877

TABLE 3C 1.2 mm flame Dosage p (FTP) @ V1 Run Batch # J/cm2 2 day 7 dayAvg 1 B-15 36 0.5719 1.0000 0.7859 2 B-6 21 1.0000 0.7562 0.8781 3 B-136 0.0558 0.0576 0.0567 4 B-9 36 0.7610 1.0000 0.8805 5 B-13 6 0.12060.4050 0.2628 6 B-15 6 0.0007 0.0000 0.0004 7 B-5 36 1.0000 1.00001.0000 8 B-15 6 0.0118 0.0000 0.0059 9 B-1 36 0.2842 0.9951 0.6397 10B-16 36 0.9929 0.9954 0.9942 11 B-15 36 0.5716 0.9987 0.7852 12 B-14 60.4127 0.2699 0.3413 13 B-5 6 1.0000 0.5441 0.7720 14 B-9 21 0.00410.9840 0.4941 15 B-16 6 0.4097 0.5567 0.4832 16 B-4 6 0.7680 0.01180.3899 17 B-5 6 0.7686 0.4054 0.5870 19 B-9 21 0.9991 0.9991 0.9991 20B-14 21 0.7672 1.0000 0.8836 21 B-11 6 0.0000 0.0000 0.0000 22 B-11 360.0309 0.7597 0.3953 23 B-7 6 0.0000 0.0289 0.0145 24 B-11 36 0.00000.9498 0.4749 25 B-11 6 0.0312 0.0000 0.0156 26 B-16 36 0.7663 0.76860.7675 27 B-15 36 1.0000 0.7683 0.8841 28 B-10 6 0.5209 0.7379 0.6294 29B-12 36 0.7686 0.9997 0.8842 30 B-5 36 1.0000 1.0000 1.0000 31 B-1 210.0290 0.0129 0.0210 32 B-2 6 0.0041 0.0000 0.0021 33 B-13 21 0.00000.5729 0.2865 34 B-15 21 0.1849 0.7618 0.4734 35 B-12 6 0.0631 0.28460.1739 36 B-14 6 0.5715 0.3943 0.4829 37 B-8 36 0.7657 0.9905 0.8781 39B-6 36 0.9999 0.9748 0.9874 40 B-2 36 0.7685 0.7562 0.7624 41 B-3 211.0000 0.7682 0.8841

TABLE 3D Tensile bars for chem (6 bars @ 1% strain) Elongation at BreakRE Batch Dosage No UV, No UV, UV, No UV, % (UV, Run # J/cm² No Chem AceChem Ace Ace) 1 B-15 36 — 0 56.72 44.01 77.59 2 B-6 21 104.06 0 94.5716.95 17.92 3 B-13 6 109.28 0 100.73 0.00 0.00 4 B-9 36 111.23 0 80.3181.56 101.56 5 B-13 6 109.28 0 96.7 0.00 0.00 6 B-15 6 96.15 0 86.020.00 0.00 7 B-5 36 102.22 0 88.88 89.35 100.53 8 B-15 6 96.15 0 86.969.28 10.67 9 B-1 36 110.66 0 101.18 70.69 69.87 10 B-16 36 99.46 0 74.8664.38 86.00 11 B-15 36 96.15 0 65.73 59.28 90.19 12 B-14 6 107.33 0 93.71.60 1.70 13 B-5 6 102.22 0 95.48 2.19 2.29 14 B-9 21 111.23 0 85.7445.43 52.98 15 B-16 6 99.46 0 — 0.00 0.00 16 B-4 6 112.78 0 108.42 0.340.31 17 B-5 6 102.22 0 94.07 1.88 2.00 19 B-9 21 111.23 0 85.89 65.9976.83 20 B-14 21 107.33 0 87.09 27.39 31.45 21 B-11 6 112.65 0 89.710.00 0.00 22 B-11 36 112.65 0 57.45 33.07 57.56 23 B-7 6 110.60 0 92.850.00 0.00 24 B-11 36 112.65 0 57.61 23.18 40.24 25 B-11 6 112.65 0 —0.00 0.00 26 B-16 36 99.46 0 74.94 64.27 85.76 27 B-15 36 96.15 0 61.6761.07 99.03 28 B-10 6 103.14 0 94.91 0.38 0.40 29 B-12 36 110.34 0 64.8136.16 55.79 30 B-5 36 102.22 0 93.86 72.12 76.84 31 B-1 21 110.66 0102.65 29.72 28.95 32 B-2 6 112.41 0 104.47 0.00 0.00 33 B-13 21 109.280 88.25 65.56 74.29 34 B-15 21 96.15 0 77.45 24.36 31.45 35 B-12 6110.34 0 93.25 3.02 0.06 36 B-14 6 107.33 0 91.79 4.26 4.64 37 B-8 36112.24 0 88.53 59.97 67.74 39 B-6 36 104.06 0 94.15 79.70 84.65 40 B-236 112.41 0 91.36 23.63 25.86 41 B-3 21 115.00 0 95.73 8.28 8.65

TABLE 3E Dosage YI % T Run Batch # J/cm² Before UV After UV Delta BeforeUV After UV Delta 1 B-15 36 8.48 17.00 8.52 86.32 82.47 −3.85 2 B-6 212.28 9.42 7.14 88.95 85.82 −3.14 3 B-13 6 4.25 6.25 2.00 88.34 87.21−1.12 4 B-9 36 4.71 16.36 11.65 87.83 82.78 −5.05 5 B-13 6 4.25 6.642.39 88.34 87.16 −1.18 6 B-15 6 8.48 10.84 2.36 86.32 85.26 −1.06 7 B-536 3.69 14.22 10.53 88.06 83.49 −4.56 8 B-15 6 8.48 10.72 2.24 86.3285.37 −0.95 9 B-1 36 3.32 10.30 6.99 88.34 85.30 −3.05 10 B-16 36 5.2418.65 13.42 87.97 82.16 −5.81 11 B-15 36 8.48 27.25 18.77 86.32 78.23−8.09 12 B-14 6 5.36 7.68 2.32 87.78 86.63 −1.15 13 B-5 6 3.69 5.66 1.9788.06 87.16 −0.89 14 B-9 21 4.71 10.77 6.06 87.83 85.06 −2.77 15 B-16 65.24 7.54 2.31 87.97 86.78 −1.19 16 B-4 6 2.33 4.41 2.08 88.88 87.97−0.92 17 B-5 6 3.69 5.60 1.91 88.06 87.08 −0.98 19 B-9 21 4.71 12.427.71 87.83 84.28 −3.55 20 B-14 21 5.36 12.78 7.41 87.78 84.41 −3.37 21B-11 6 6.52 8.64 2.12 87.17 86.02 −1.14 22 B-11 36 6.52 18.72 12.2187.17 81.40 −5.77 23 B-7 6 4.77 7.25 2.48 87.62 86.46 −1.16 24 B-11 366.52 20.29 13.77 87.17 80.79 −6.37 25 B-11 6 6.52 8.79 2.28 87.17 85.91−1.26 26 B-16 36 5.24 15.64 10.40 87.97 83.19 −4.79 27 B-15 36 8.4816.59 8.11 86.32 82.53 −3.79 28 B-10 6 5.20 7.69 2.49 87.57 86.60 −0.9729 B-12 36 5.11 14.65 9.54 87.86 83.36 −4.50 30 B-5 36 3.69 12.04 8.3588.06 84.43 −3.63 31 B-1 21 3.32 7.94 4.63 88.34 86.28 −2.06 32 B-2 62.06 3.85 1.79 89.04 88.15 −0.89 33 B-13 21 4.25 12.16 7.91 88.34 84.63−3.70 34 B-15 21 8.48 14.57 6.09 86.32 83.47 −2.85 35 B-12 6 5.11 7.362.25 87.86 86.71 −1.15 36 B-14 6 5.36 7.92 2.55 87.78 86.71 −1.07 37 B-836 3.07 10.65 7.59 88.41 85.16 −3.25 39 B-6 36 2.28 8.58 6.30 88.9586.30 −2.65 40 B-2 36 2.06 8.62 6.56 89.04 86.34 −2.70 41 B-3 21 2.938.34 5.41 88.30 85.86 −2.44

TABLE 3F Dosage XPC MFR Run Batch # J/cm² wt % g/10 min 1 B-15 36 21.396.04 2 B-6 21 1.33 6.07 3 B-13 6 10.22 11.3 4 B-9 36 8.68 9.23 5 B-13 610.22 11.3 6 B-15 6 21.39 6.04 7 B-5 36 2.65 5.55 8 B-15 6 21.39 6.04 9B-1 36 2.63 19.8 10 B-16 36 10.87 6.38 11 B-15 36 21.39 6.04 12 B-14 610.84 8.65 13 B-5 6 2.65 5.55 14 B-9 21 8.68 9.23 15 B-16 6 10.87 6.3816 B-4 6 1.32 8.52 17 B-5 6 2.65 5.55 19 B-9 21 8.68 9.23 20 B-14 2110.84 8.65 21 B-11 6 20.25 17.6 22 B-11 36 20.25 17.6 23 B-7 6 10.8316.2 24 B-11 36 20.25 17.6 25 B-11 6 20.25 17.6 26 B-16 36 10.87 6.38 27B-15 36 21.39 6.04 28 B-10 6 5.84 6.63 29 B-12 36 15.18 13.6 30 B-5 362.65 5.55 31 B-1 21 2.63 19.8 32 B-2 6 1.3 11.3 33 B-13 21 10.22 11.3 34B-15 21 21.39 6.04 35 B-12 6 15.18 13.6 36 B-14 6 10.84 8.65 37 B-8 365.32 10.8 39 B-6 36 1.33 6.07 40 B-2 36 1.3 11.3 41 B-3 21 1.96 9.12

The five predictive model equations discussed above were based on the 40samples described in Tables 3A-F. They can be used to designpolycarbonates that will consistently (A) pass the UL94 V0 test, eitherafter 2 days or 7 days of conditioning and (B) provide high percentageretention of tensile elongation following exposure to acetone while (C)minimizing the color shift due to UV exposure. The equations wereobtained using Design-Expert® version 7.0.3 from Stat-Ease, Inc.

FIG. 4 is a graph showing the model equation for the average V0(Equation 1). Again, this is the average of the pFTP value obtained byaveraging the V0 test at 2 days and the V0 test for 7 days. The MFR isheld constant at 7.65, the blend level (i.e. weight percentage ofcrosslinkable resin, WP) is held constant at 75%, and the molecularweight increase is held constant at 5500. The resulting curves show thepredicted average V0 for various combinations of UV dosage and amount ofDHBP (MOL %). The lower-right triangle below the 0.897353 line showscombinations that should have a high average V0, and is the desireddesign space.

FIG. 5 is a graph showing the model equation for the delta YI (Equation3). The molecular weight increase is held constant at 2000. Theresulting curves show the predicted delta YI for various combinations ofUV dosage and amount of DHBP (MOL %). The area to the left of the 3.7037line shows combinations that should have a low Delta YI, and is thedesired design space.

FIG. 6 is a graph showing the model equation for the percentageretention of tensile elongation, % RE (Equation 2). The MFR is heldconstant at 12.68, the WP is held constant at 75%, and the dosage isheld constant at 6 J/cm². The resulting curves show the predicted % REfor various combinations of molecular weight increase and MOL %. Theupper-right area is the desired design space.

FIG. 7 is a graph that is identical to FIG. 6, except that the dosage isheld constant at 36 J/cm². Comparing FIG. 6 to FIG. 7, there is a largedifference now in the acceptable design spaces. There is now alower-left area as well as the upper-right area, and both areas are alsorelatively larger.

FIG. 8 is a graph that illustrates the combination of three modelequations to identify a design space. The simulated article is formedfrom 100% of a crosslinkable polycarbonate containing 20 mole % ofrepeating units derived from 4,4′-dihydroxybenzophenone. In other words,WP=100 and MOL %=20. The MF is also set to 5.74. Model Equations 1, 2,and 3 are used. The x-axis is the UV dose, D, and the y-axis is themolecular weight increase, MW_I. The equations can then be used todetermine the design space where the % RE will be greater than 85%, thedelta YI will be less than 6, and the average V0 will be greater than0.7. The area above the horizontal line denotes the space where the %retention of elongation is greater than 85%. The area under the curvedenotes the space where the delta YI of less than 6 can be obtained. Thearea above the top slanted line, and the area below the lower slantedline, each denote the space where the average V0 will be greater than0.7. Their intersection (i.e. the triangle in the left center) providesthe design space (combination of UV dose and molecular weight increase)needed to obtain these three desired properties.

FIG. 9 is another graph that illustrates the combination of three modelequations to identify a design space. Here, the simulated article isformed from 100% of a crosslinkable polycarbonate containing 10 mole %of repeating units derived from 4,4′-dihydroxybenzophenone. In otherwords, WP=100 and MOL %=10. The MF is also set to 5.55. The x-axis isthe UV dose, D, and the y-axis is the molecular weight increase, MW_I.The equations are again used to determine the design space where the %RE will be greater than 85%, the delta YI will be less than 6, and theaverage V0 will be greater than 0.7. This time, however, the designspace is in two different locations. One location indicates a UV dosageof approximately 6 to 13.5 and a molecular weight increase ofapproximately 6000 to 8400. The second location indicates a UV dosage ofapproximately 18 to 26 and a molecular weight increase of approximately0 to 2750.

FIG. 10 is yet another graph that illustrates the combination of threemodel equations to identify a design space. Here, the simulated articleis formed from 100% of a crosslinkable polycarbonate containing 5 mole %of repeating units derived from 4,4′-dihydroxybenzophenone. In otherwords, WP=100 and MOL %=5. The MF is still set to 5.55. The equationsare again used to determine the design space where the % RE will begreater than 85%, the delta YI will be less than 6, and the average V0will be greater than 0.7. The design spaces are very similar to FIG. 9,but slightly smaller in area.

FIG. 11 is another graph that illustrates the combination of three modelequations to identify a design space. The simulated article is formedfrom a blend containing 50 wt % of a crosslinkable polycarbonatecontaining 5 mole % of repeating units derived from4,4′-dihydroxybenzophenone, and 50 wt % of a bisphenol-Ahomopolycarbonate having a weight-average molecular weight of about31,000. Thus, WP=50 and MOL %=5. The MF is now set to 4.84. Theequations are again used to determine the design space where the % REwill be greater than 85%, the delta YI will be less than 6, and theaverage V0 will be greater than 0.7. Now compared to FIG. 10, only thebottom design space will achieve the desired combination of properties.

The above formulations and equations can be used to design polycarbonatearticles that have desired properties and provide means for identifyinghow changes in the polymers used to make the articles will affect theresulting properties of the articles.

Set forth below are some embodiments of the process and articlesdisclosed herein.

Embodiment 1

A process for preparing an article that has a high probability ofpassing a UL94 V0 test, comprising:

-   -   (A) providing a polymeric composition to be exposed to a        dosage (D) of UVA radiation, wherein the polymeric composition        comprises:        -   (i) a cross-linkable polycarbonate resin including repeating            units derived from a dihydroxybenzophenone;        -   (ii) a flame retardant; and        -   (iii) optionally one or more polymeric base resins;        -   (iv) wherein the cross-linkable polycarbonate resin contains            a molar percentage of the dihydroxybenzophenone (MOL %); and        -   (v) wherein the polymeric composition has:            -   (a) a molecular weight increase of polymeric components                therein after exposure to UV radiation (MW_I),            -   (b) a melt flow rate (MF), and            -   (c) a weight percentage of the cross-linkable                polycarbonate resin (WP);    -   (B) forming an article from the polymeric composition; and    -   (C) exposing the formed article to the dosage;        wherein D, MOL %, MW_I, MF, and WP are determined based on a        flame performance equation as follows:

Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL %)²)−(0.017115×(MF)²)

wherein the article has an average V0 (V0_Avg) that is the average of:

-   -   (i) the probability of a first time pass in a UL94 V0 test at a        thickness of 1.2 mm after UV exposure measured after 2 days of        aging at room temperature, and    -   (ii) the probability of a first time pass in a UL94 V0 test at a        thickness of 1.2 mm after UV exposure measured after 7 days of        aging at 70° C.; and        wherein V0_Avg is at least 0.7; and        wherein D is measured in J/cm² of UVA radiation.

Embodiment 2

The process of Embodiment 1, wherein (a) D, MOL %, MW_I, WP, and MF arealso determined based on a percentage retention of tensile elongationequation as follows:

Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL %)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)

wherein % RE is the percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm; and % RE is at least 85;or

-   -   (b) wherein D, MOL %, and MW_I are also determined based on a        Delta YI equation as follows:

Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I)

wherein D_YI is the change in YI after exposure to the dosage D,measured before UVA exposure and at least 48 hours after UVA exposure;and D_YI is 6 or less; or

-   -   (c) wherein D, MOL %, MW_I, and MF are also determined based on        a Delta % T equation as follows:

(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF)

wherein D_% T is the change in light transmission after exposure to thedosage D, measured before UVA exposure and at least 48 hours after UVAexposure; and D_% T is 3.5 or less; or

-   -   (d) wherein D, MOL %, MW_I, MF, and WP are also determined based        on a gel thickness equation as follows:

Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²)

wherein GEL is the gel thickness on a surface of the article, measuredin micrometers, and is at least 5.

Embodiment 3

The process of any one of Embodiments 1-2, wherein the polymericcomposition comprises a polymeric base resin.

Embodiment 4

The process of any one of Embodiments 1-3, wherein MOL % is from 2.5 to20; or wherein MW_I is from about 600 to about 11,000; or wherein MF isfrom about 5 to about 20; or wherein WP is from 50 to 100.

Embodiment 5

The process of any one of Embodiments 1-4, wherein the cross-linkablepolycarbonate resin is a copolymer or a terpolymer.

Embodiment 6

The article formed by the process of any one of Embodiments 1-5,wherein:

-   -   (a) the article has a V0_Avg of at least 0.7, a percentage        retention of tensile elongation (% RE) of at least 85, and a        Delta YI of less than 6; or    -   (b) the article is a molded article, a film, a sheet, a layer of        a multilayer film, or a layer of a multilayer sheet.

Embodiment 7

A process for preparing an article that has a desired percentageretention of tensile elongation after exposure to acetone at a thicknessof 3.2 mm, comprising:

-   -   (A) providing a polymeric composition to be exposed to a        dosage (D) of UVA radiation, wherein the polymeric composition        comprises:        -   (iii) a cross-linkable polycarbonate resin including            repeating units derived from a dihydroxybenzophenone;        -   (iv) a flame retardant; and        -   (v) optionally one or more polymeric base resins;        -   (vi) wherein the cross-linkable polycarbonate resin contains            a selectable molar percentage of the dihydroxybenzophenone            (MOL %); and        -   (vii) wherein the polymeric composition has:            -   (a) a molecular weight increase of polymeric components                therein after exposure to UV radiation (MW_I),            -   (b) a melt flow rate (MF), and            -   (c) a weight percentage of the cross-linkable                polycarbonate resin (WP);    -   (B) forming an article from the polymeric composition; and    -   (C) exposing the formed article to the dosage;        wherein D, MOL %, MW_I, MF, and WP are determined based on a        percentage retention of tensile elongation equation as follows:

Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL %)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)

wherein % RE is the percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm; and % RE is at least 85.

Embodiment 8

The process of Embodiment 7, wherein (a) D, MOL %, MW_I, WP, and MF arealso determined based on a flame performance equation as follows:

Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL %)²)−(0.017115×(MF)²)

wherein the article has an average V0 (V0_Avg) that is the average of(i) the probability of a first time pass in a UL94 V0 test at athickness of 1.2 mm after UV exposure and measured after 2 days of agingat room temperature, and (ii) the probability of a first time pass in aUL94 V0 test at a thickness of 1.2 mm after UV exposure and measuredafter 7 days of aging at 70° C.; and V0_Avg is at least 0.7; wherein Dis measured in J/cm² of UVA radiation; or

-   -   (b) wherein D, MOL %, and MW_I are also determined based on a        Delta YI equation as follows:

Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I)

wherein D_YI is the change in YI after exposure to the dosage D,measured before UVA exposure and at least 48 hours after UVA exposure;and D_YI is 6 or less; or

-   -   (c) wherein D, MOL %, MW_I, and MF are also determined based on        a Delta % T equation as follows:

(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF)

wherein D_% T is the change in light transmission after exposure to thedosage D, measured before UVA exposure and at least 48 hours after UVAexposure; and D_% T is 3.5 or less; or

-   -   (d) wherein D, MOL %, MW_I, MF, and WP are also determined based        on a gel thickness equation as follows:

Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²)

wherein GEL is the gel thickness on a surface of the article, measuredin micrometers, and is at least 5.

Embodiment 9

The process of any one of Embodiments 7-8, wherein the polymericcomposition comprises a polymeric base resin.

Embodiment 10

The process of any one of Embodiments 7-9, wherein MOL % is from 2.5 to20; or wherein MW_I is from about 600 to about 11,000; or wherein MF isfrom about 5 to about 20; or wherein WP is from 50 to 100.

Embodiment 11

The process of any one of Embodiments 7-10, wherein the cross-linkablepolycarbonate resin is a copolymer or a terpolymer.

Embodiment 12

The article formed by the process of any one of Embodiments 7-11;wherein

-   -   (a) the article has an average V0 of at least 0.7, a percentage        retention of tensile elongation (% RE) of at least 85, and a        Delta YI of 6 or less; or    -   (b) the article is a molded article, a film, a sheet, a layer of        a multilayer film, or a layer of a multilayer sheet.

Embodiment 13

A process for preparing an article that has a low Delta YI afterexposure to UVA radiation, comprising:

-   -   (A) providing a polymeric composition to be exposed to a        dosage (D) of UVA radiation, wherein the polymeric composition        comprises:        -   (viii) a cross-linkable polycarbonate resin including            repeating units derived from a dihydroxybenzophenone;        -   (ix) a flame retardant; and        -   (x) optionally one or more polymeric base resins;        -   (xi) wherein the cross-linkable polycarbonate resin contains            a selectable molar percentage of the dihydroxybenzophenone            (MOL %); and        -   (xii) wherein the polymeric composition has:        -   (xiii) a molecular weight increase of polymeric components            therein after exposure to UV radiation (MW_I),        -   (xiv) a melt flow rate (MF), and        -   (xv) a weight percentage of the cross-linkable polycarbonate            resin (WP);    -   (B) forming an article from the polymeric composition; and    -   (C) exposing the formed article to the dosage;        wherein D, MOL %, and MW_I are determined based on a Delta YI        equation as follows:

Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I)

wherein D_YI is the change in YI after exposure to the dosage D,measured before UVA exposure and at least 48 hours after UVA exposure;and D_YI is 6 or less.

Embodiment 14

The process of Embodiment 13, wherein (a) D, MOL %, MW_I, WP, and MF arealso determined based on a flame performance equation as follows:

Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL %)²)−(0.017115×(MF)²)

wherein the article has an average V0 (V0_Avg) that is the average of(i) the probability of a first time pass in a UL94 V0 test at athickness of 1.2 mm after UV exposure and measured after 2 days of agingat room temperature, and (ii) the probability of a first time pass in aUL94 V0 test at a thickness of 1.2 mm after UV exposure and measuredafter 7 days of aging at 70° C.; and V0_Avg is at least 0.7; wherein Dis measured in J/cm² of UVA radiation; or

-   -   (b) wherein D, MOL %, MW_I, WP, and MF are also determined based        on a percentage retention of tensile elongation equation as        follows:

Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL %)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)

wherein % RE is the percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm; and % RE is at least 85;or

-   -   (c) wherein D, MOL %, MW_I, and MF are also determined based on        a Delta % T equation as follows:

(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF)

wherein D_% T is the change in light transmission after exposure to thedosage D, measured before UVA exposure and at least 48 hours after UVAexposure; and D_% T is 3.5 or less; or

-   -   (d) wherein D, MOL %, MW_I, MF, and WP are also determined based        on a gel thickness equation as follows:

Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²)

wherein GEL is the gel thickness on a surface of the article, measuredin micrometers, and is at least 5.

Embodiment 15

The process of any one of Embodiments 13-14, wherein the polymericcomposition comprises a polymeric base resin.

Embodiment 16

The process of any one of Embodiments 13-15, wherein MOL % is from 2.5to 20; or wherein MW_I is from about 600 to about 11,000; or wherein MFis from about 5 to about 20; or wherein WP is from 50 to 100.

Embodiment 17

The process of any one of Embodiments 13-16, wherein the cross-linkablepolycarbonate resin is a copolymer or a terpolymer.

Embodiment 18

The article formed by the process of any one of Embodiments 13-17,wherein:

-   -   (a) the article has an average V0 of at least 0.7, a percentage        retention of tensile elongation (% RE) of at least 85, and a        Delta YI of 6 or less; or    -   (b) the article is a molded article, a film, a sheet, a layer of        a multilayer film, or a layer of a multilayer sheet.

Embodiment 19

An article formed from a polymeric composition that comprises (i) across-linkable polycarbonate resin including repeating units derivedfrom a dihydroxybenzophenone, and (ii) a flame retardant;

-   -   wherein the article has a pFTP(V0) of at least 0.9 at a        thickness of 1.2 mm after UV exposure and measured after 2 days        of aging at room temperature; and    -   wherein the article has a percentage retention of tensile        elongation of at least 85% after exposure to acetone at a        thickness of 3.2 mm; and    -   optionally wherein the article also has a Delta YI of less than        10, measured before UVA exposure and at least 48 hours after UVA        exposure.

Embodiment 20

An article formed from a polymeric composition that comprises across-linkable polycarbonate resin including repeating units derivedfrom a dihydroxybenzophenone, and a flame retardant;

-   -   (a) wherein the article (i) has a pFTP(V0) of at least 0.9 at a        thickness of 1.2 mm after UV exposure and measured after 2 days        of aging at room temperature; and (ii) has a Delta YI of less        than 10, measured before UVA exposure and at least 48 hours        after UVA exposure; or    -   (b) wherein the article (i) has a percentage retention of        tensile elongation of at least 85% after exposure to acetone at        a thickness of 3.2 mm; and (ii) has a Delta YI of less than 10,        measured before UVA exposure and at least 48 hours after UVA        exposure.

The present disclosure has been described with reference to exemplaryembodiments. Obviously, modifications and alterations will occur toothers upon reading and understanding the preceding detaileddescription. It is intended that the present disclosure be construed asincluding all such modifications and alterations insofar as they comewithin the scope of the appended claims or the equivalents thereof.

1. A process for preparing an article that has a high probability ofpassing a UL94 V0 test, comprising: (A) providing a polymericcomposition to be exposed to a dosage (D) of UVA radiation, wherein thepolymeric composition comprises: (i) a cross-linkable polycarbonateresin including repeating units derived from a dihydroxybenzophenone;(ii) a flame retardant; and (iii) optionally one or more polymeric baseresins; (iv) wherein the cross-linkable polycarbonate resin contains amolar percentage of the dihydroxybenzophenone (MOL %); and (v) whereinthe polymeric composition has: (a) a molecular weight increase ofpolymeric components therein after exposure to UV radiation (MW_I), (b)a melt flow rate (MF), and (c) a weight percentage of the cross-linkablepolycarbonate resin (WP); (B) forming an article from the polymericcomposition; and (C) exposing the formed article to the dosage; whereinD, MOL %, MW_I, MF, and WP are determined based on a flame performanceequation as follows:Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL %)²)−(0.017115×(MF)²)wherein the article has an average V0 (V0_Avg) that is the average of:(i) the probability of a first time pass in a UL94 V0 test at athickness of 1.2 mm after UV exposure measured after 2 days of aging atroom temperature, and (ii) the probability of a first time pass in aUL94 V0 test at a thickness of 1.2 mm after UV exposure measured after 7days of aging at 70° C.; and wherein V0_Avg is at least 0.7; and whereinD is measured in J/cm² of UVA radiation.
 2. The process of claim 1,wherein (a) D, MOL %, MW_I, WP, and MF are also determined based on apercentage retention of tensile elongation equation as follows:Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL %)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)wherein % RE is the percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm; and % RE is at least 85;or (b) wherein D, MOL %, and MW_I are also determined based on a DeltaYI equation as follows:Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I) wherein D_YI is the change in YI after exposureto the dosage D, measured before UVA exposure and at least 48 hoursafter UVA exposure; and D_YI is 6 or less; or (c) wherein D, MOL %,MW_I, and MF are also determined based on a Delta % T equation asfollows:(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF) wherein D_% T is the change in lighttransmission after exposure to the dosage D, measured before UVAexposure and at least 48 hours after UVA exposure; and D_% T is 3.5 orless; or (d) wherein D, MOL %, MW_I, MF, and WP are also determinedbased on a gel thickness equation as follows:Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²) wherein GEL is the gelthickness on a surface of the article, measured in microns, and is atleast
 5. 3. The process of claim 1, wherein the polymeric compositioncomprises a polymeric base resin.
 4. The process of claim 1, wherein MOL% is from 2.5 to 20; or wherein MW_I is from about 600 to about 11,000;or wherein MF is from about 5 to about 20; or wherein WP is from 50 to100.
 5. The process of claim 1, wherein the cross-linkable polycarbonateresin is a copolymer or a terpolymer.
 6. The article formed by theprocess of claim 1, wherein: (a) the article has a V0_Avg of at least0.7, a percentage retention of tensile elongation (% RE) of at least 85,and a Delta YI of less than 6; or (b) the article is a molded article, afilm, a sheet, a layer of a multilayer film or a layer of a multilayersheet.
 7. A process for preparing an article that has a desiredpercentage retention of tensile elongation after exposure to acetone ata thickness of 3.2 mm, comprising: (A) providing a polymeric compositionto be exposed to a dosage (D) of UVA radiation, wherein the polymericcomposition comprises: (i) a cross-linkable polycarbonate resinincluding repeating units derived from a dihydroxybenzophenone; (ii) aflame retardant; and (iii) optionally one or more polymeric base resins;(iv) wherein the cross-linkable polycarbonate resin contains aselectable molar percentage of the dihydroxybenzophenone (MOL %); and(v) wherein the polymeric composition has: (a) a molecular weightincrease of polymeric components therein after exposure to UV radiation(MW_I), (b) a melt flow rate (MF), and (c) a weight percentage of thecross-linkable polycarbonate resin (WP); (B) forming an article from thepolymeric composition; and (C) exposing the formed article to thedosage; wherein D, MOL %, MW_I, MF, and WP are determined based on apercentage retention of tensile elongation equation as follows:Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL %)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)wherein % RE is the percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm; and % RE is at least 85.8. The process of claim 7, wherein (a) D, MOL %, MW_I, WP, and MF arealso determined based on a flame performance equation as follows:Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL %)²)−(0.017115×(MF)²)wherein the article has an average V0 (V0_Avg) that is the average of(i) the probability of a first time pass in a UL94 V0 test at athickness of 1.2 mm after UV exposure and measured after 2 days of agingat room temperature, and (ii) the probability of a first time pass in aUL94 V0 test at a thickness of 1.2 mm after UV exposure and measuredafter 7 days of aging at 70° C.; and V0_Avg is at least 0.7; wherein Dis measured in J/cm² of UVA radiation; or (b) wherein D, MOL %, and MW_Iare also determined based on a Delta YI equation as follows:Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I) wherein D_YI is the change in YI after exposureto the dosage D, measured before UVA exposure and at least 48 hoursafter UVA exposure; and D_YI is 6 or less; or (c) wherein D, MOL %,MW_I, and MF are also determined based on a Delta % T equation asfollows:(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF) wherein D_% T is the change in lighttransmission after exposure to the dosage D, measured before UVAexposure and at least 48 hours after UVA exposure; and D_% T is 3.5 orless; or (d) wherein D, MOL %, MW_I, MF, and WP are also determinedbased on a gel thickness equation as follows:Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²) wherein GEL is the gelthickness on a surface of the article, measured in microns, and is atleast
 5. 9. The process of claim 7, wherein the polymeric compositioncomprises a polymeric base resin.
 10. The process of claim 7, whereinMOL % is from 2.5 to 20; or wherein MW_I is from about 600 to about11,000; or wherein MF is from about 5 to about 20; or wherein WP is from50 to
 100. 11. The process of claim 7, wherein the cross-linkablepolycarbonate resin is a copolymer or a terpolymer.
 12. The articleformed by the process of claim 7, wherein: (a) the article has anaverage V0 of at least 0.7, a percentage retention of tensile elongation(% RE) of at least 85, and a Delta YI of 6 or less; or (b) the articleis a molded article, a film, a sheet, a layer of a multilayer film, or alayer of a multilayer sheet.
 13. A process for preparing an article thathas a low Delta YI after exposure to UVA radiation, comprising: (A)providing a polymeric composition to be exposed to a dosage (D) of UVAradiation, wherein the polymeric composition comprises: (i) across-linkable polycarbonate resin including repeating units derivedfrom a dihydroxybenzophenone; (ii) a flame retardant; and (iii)optionally one or more polymeric base resins; (iv) wherein thecross-linkable polycarbonate resin contains a selectable molarpercentage of the dihydroxybenzophenone (MOL %); and (v) wherein thepolymeric composition has: (vi) a molecular weight increase of polymericcomponents therein after exposure to UV radiation (MW_I), (vii) a meltflow rate (MF), and (viii) a weight percentage of the cross-linkablepolycarbonate resin (WP); (B) forming an article from the polymericcomposition; and (C) exposing the formed article to the dosage; whereinD, MOL %, and MW_I are determined based on a Delta YI equation asfollows:Ln(D_YI)=−0.047177+(0.062393×D+1.81716×10⁻⁴×MW_I)+(0.017370×MOL%)−(5.48288×10⁻⁶×D×MW_I) wherein D_YI is the change in YI after exposureto the dosage D, measured before UVA exposure and at least 48 hoursafter UVA exposure; and D_YI is 6 or less.
 14. The process of claim 13,wherein (a) D, MOL %, MW_I, WP, and MF are also determined based on aflame performance equation as follows:Sqrt(V0_Avg)=−0.62315+(9.21942×10⁻³×WP)+(0.041498×D)+(4.34876×10⁻⁵×MW_I)+(6.55546×10⁻³×MOL%)+(0.089017×MF)+(9.87122×10⁻⁴×WP×D)−(4.36994×10⁻⁶×WP×MW_I)−(2.43440×10⁻³×WP×MOL%)+(2.08870×10⁻³×WP×MF)−(4.40362×10⁻⁶×D×MW_I)−(2.32567×10⁻³×D×MOL%)−(3.75290×10⁻³×D×MF)+(2.05611×10⁻⁵×MW_I×MF)+(5.61409×10⁻³×MOL%×MF)+(2.98567×10⁻⁹×(MW_I)²)+(6.17229×10⁻³×(MOL %)²)−(0.017115×(MF)²)wherein the article has an average V0 (V0_Avg) that is the average of(i) the probability of a first time pass in a UL94 V0 test at athickness of 1.2 mm after UV exposure and measured after 2 days of agingat room temperature, and (ii) the probability of a first time pass in aUL94 V0 test at a thickness of 1.2 mm after UV exposure and measuredafter 7 days of aging at 70° C.; and V0_Avg is at least 0.7; wherein Dis measured in J/cm² of UVA radiation; or (b) wherein D, MOL %, MW_I,WP, and MF are also determined based on a percentage retention oftensile elongation equation as follows:Sqrt(%RE)=+1.37235+(0.077638×WP)+(0.67685×D)−(2.39234×10⁻³×MW_I)−(0.23516×MOL%)−(0.57165×MF)−(9.18615×10⁻³×WP×MF)−(6.66016×10⁻⁵×D×MW_I)−(0.019526×D×MOL%)+(2.07809×10⁻⁴×MW_I×MOL %)+(2.79873×10⁻⁷×(MW_I)²)+(0.056758×(MF)²)wherein % RE is the percentage retention of tensile elongation afterexposure to acetone at a thickness of 3.2 mm; and % RE is at least 85;or (c) wherein D, MOL %, MW_I, and MF are also determined based on aDelta % T equation as follows:(D_% T+8.90)^(2.65)=+343.92310−(6.75832×D)−(0.022788×MW_I)+(0.43933×MOL%)−(3.84042×MF)+(5.56692×10⁻⁴×D×MW_I)−(8.77565×10⁻⁴×MW_I×MOL%)+(8.94844×10⁻⁴×MW_I×MF) wherein D_% T is the change in lighttransmission after exposure to the dosage D, measured before UVAexposure and at least 48 hours after UVA exposure; and D_% T is 3.5 orless; or (d) wherein D, MOL %, MW_I, MF, and WP are also determinedbased on a gel thickness equation as follows:Sqrt(GEL)=+2.69872−(0.093035×WP)+(0.31583×D)−(5.37830×10⁻⁴×MW_I)+(0.28207×MOL%)−(0.092447×MF)−(2.29409×10⁻³×WP×D)+(2.03257×10⁻⁵×WP×MW_I)+(0.010073×WP×MOL%)−(1.01623×10⁻⁷×(MW_I)²)−(0.043959×(MOL %)²) wherein GEL is the gelthickness on a surface of the article, measured in microns, and is atleast
 5. 15. The process of claim 13, wherein the polymeric compositioncomprises a polymeric base resin.
 16. The process of claim 13, whereinMOL % is from 2.5 to 20; or wherein MW_I is from about 600 to about11,000; or wherein MF is from about 5 to about 20; or wherein WP is from50 to
 100. 17. The process of claim 13, wherein the cross-linkablepolycarbonate resin is a copolymer or a terpolymer.
 18. The articleformed by the process of claim 13, wherein: (a) the article has anaverage V0 of at least 0.7, a percentage retention of tensile elongation(% RE) of at least 85, and a Delta YI of 6 or less; or (b) the articleis a molded article, a film, a sheet, a layer of a multilayer film, or alayer of a multilayer sheet.
 19. An article formed from a polymericcomposition that comprises (i) a cross-linkable polycarbonate resinincluding repeating units derived from a dihydroxybenzophenone, and (ii)a flame retardant; wherein the article has a pFTP(V0) of at least 0.9 ata thickness of 1.2 mm after UV exposure and measured after 2 days ofaging at room temperature; and wherein the article has a percentageretention of tensile elongation of at least 85% after exposure toacetone at a thickness of 3.2 mm; and optionally wherein the articlealso has a Delta YI of less than 10, measured before UVA exposure and atleast 48 hours after UVA exposure.
 20. An article formed from apolymeric composition that comprises a cross-linkable polycarbonateresin including repeating units derived from a dihydroxybenzophenone,and a flame retardant; (a) wherein the article (i) has a pFTP(V0) of atleast 0.9 at a thickness of 1.2 mm after UV exposure and measured after2 days of aging at room temperature; and (ii) has a Delta YI of lessthan 10, measured before UVA exposure and at least 48 hours after UVAexposure; or (b) wherein the article (i) has a percentage retention oftensile elongation of at least 85% after exposure to acetone at athickness of 3.2 mm; and (ii) has a Delta YI of less than 10, measuredbefore UVA exposure and at least 48 hours after UVA exposure.